Adding upstream version 9.1.upstream/9.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 4947 insertions, 0 deletions

diff --git a/isisd/isis_nb_config.c b/isisd/isis_nb_config.c
new file mode 100644
index 0000000..b6ee073
--- /dev/null
+++ b/isisd/isis_nb_config.c
@@ -0,0 +1,4947 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2001,2002   Sampo Saaristo
+ *                           Tampere University of Technology
+ *                           Institute of Communications Engineering
+ * Copyright (C) 2018        Volta Networks
+ *                           Emanuele Di Pascale
+ */
+
+#include <zebra.h>
+
+#include "printfrr.h"
+#include "northbound.h"
+#include "linklist.h"
+#include "log.h"
+#include "bfd.h"
+#include "filter.h"
+#include "plist.h"
+#include "spf_backoff.h"
+#include "lib_errors.h"
+#include "vrf.h"
+#include "ldp_sync.h"
+#include "link_state.h"
+#include "affinitymap.h"
+
+#include "isisd/isisd.h"
+#include "isisd/isis_nb.h"
+#include "isisd/isis_common.h"
+#include "isisd/isis_bfd.h"
+#include "isisd/isis_circuit.h"
+#include "isisd/isis_lsp.h"
+#include "isisd/isis_dynhn.h"
+#include "isisd/isis_misc.h"
+#include "isisd/isis_csm.h"
+#include "isisd/isis_adjacency.h"
+#include "isisd/isis_spf.h"
+#include "isisd/isis_spf_private.h"
+#include "isisd/isis_srv6.h"
+#include "isisd/isis_te.h"
+#include "isisd/isis_mt.h"
+#include "isisd/isis_redist.h"
+#include "isisd/isis_ldp_sync.h"
+#include "isisd/isis_dr.h"
+#include "isisd/isis_sr.h"
+#include "isisd/isis_flex_algo.h"
+#include "isisd/isis_zebra.h"
+
+#define AFFINITY_INCLUDE_ANY 0
+#define AFFINITY_INCLUDE_ALL 1
+#define AFFINITY_EXCLUDE_ANY 2
+
+/*
+ * XPath: /frr-isisd:isis/instance
+ */
+int isis_instance_create(struct nb_cb_create_args *args)
+{
+	struct isis_area *area;
+	const char *area_tag;
+	const char *vrf_name;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+	vrf_name = yang_dnode_get_string(args->dnode, "./vrf");
+	area_tag = yang_dnode_get_string(args->dnode, "./area-tag");
+
+	area = isis_area_lookup_by_vrf(area_tag, vrf_name);
+	if (area)
+		return NB_ERR_INCONSISTENCY;
+
+	area = isis_area_create(area_tag, vrf_name);
+
+	/* save area in dnode to avoid looking it up all the time */
+	nb_running_set_entry(args->dnode, area);
+
+	return NB_OK;
+}
+
+int isis_instance_destroy(struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+	struct isis *isis;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+	area = nb_running_unset_entry(args->dnode);
+	isis = area->isis;
+	isis_area_destroy(area);
+
+	if (listcount(isis->area_list) == 0)
+		isis_finish(isis);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/is-type
+ */
+int isis_instance_is_type_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	int type;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	type = yang_dnode_get_enum(args->dnode, NULL);
+	isis_area_is_type_set(area, type);
+
+	return NB_OK;
+}
+
+struct sysid_iter {
+	struct iso_address *addr;
+	bool same;
+};
+
+static int sysid_iter_cb(const struct lyd_node *dnode, void *arg)
+{
+	struct sysid_iter *iter = arg;
+	struct iso_address addr;
+	const char *net;
+
+	net = yang_dnode_get_string(dnode, NULL);
+	addr.addr_len = dotformat2buff(addr.area_addr, net);
+
+	if (memcmp(GETSYSID(iter->addr), GETSYSID((&addr)), ISIS_SYS_ID_LEN)) {
+		iter->same = false;
+		return YANG_ITER_STOP;
+	}
+
+	return YANG_ITER_CONTINUE;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/area-address
+ */
+int isis_instance_area_address_create(struct nb_cb_create_args *args)
+{
+	struct isis_area *area;
+	struct iso_address addr, *addrr = NULL, *addrp = NULL;
+	struct listnode *node;
+	struct sysid_iter iter;
+	uint8_t buff[255];
+	const char *net_title = yang_dnode_get_string(args->dnode, NULL);
+
+	switch (args->event) {
+	case NB_EV_VALIDATE:
+		addr.addr_len = dotformat2buff(buff, net_title);
+		memcpy(addr.area_addr, buff, addr.addr_len);
+		if (addr.area_addr[addr.addr_len - 1] != 0) {
+			snprintf(
+				args->errmsg, args->errmsg_len,
+				"nsel byte (last byte) in area address must be 0");
+			return NB_ERR_VALIDATION;
+		}
+
+		iter.addr = &addr;
+		iter.same = true;
+
+		yang_dnode_iterate(sysid_iter_cb, &iter, args->dnode,
+				   "../area-address");
+
+		if (!iter.same) {
+			snprintf(
+				args->errmsg, args->errmsg_len,
+				"System ID must not change when defining additional area addresses");
+			return NB_ERR_VALIDATION;
+		}
+		break;
+	case NB_EV_PREPARE:
+		addrr = XMALLOC(MTYPE_ISIS_AREA_ADDR,
+				sizeof(struct iso_address));
+		addrr->addr_len = dotformat2buff(buff, net_title);
+		memcpy(addrr->area_addr, buff, addrr->addr_len);
+		args->resource->ptr = addrr;
+		break;
+	case NB_EV_ABORT:
+		XFREE(MTYPE_ISIS_AREA_ADDR, args->resource->ptr);
+		break;
+	case NB_EV_APPLY:
+		area = nb_running_get_entry(args->dnode, NULL, true);
+		addrr = args->resource->ptr;
+		assert(area);
+
+		if (area->isis->sysid_set == 0) {
+			/*
+			 * First area address - get the SystemID for this router
+			 */
+			memcpy(area->isis->sysid, GETSYSID(addrr),
+			       ISIS_SYS_ID_LEN);
+			area->isis->sysid_set = 1;
+		} else {
+			/* check that we don't already have this address */
+			for (ALL_LIST_ELEMENTS_RO(area->area_addrs, node,
+						  addrp)) {
+				if ((addrp->addr_len + ISIS_SYS_ID_LEN
+				     + ISIS_NSEL_LEN)
+				    != (addrr->addr_len))
+					continue;
+				if (!memcmp(addrp->area_addr, addrr->area_addr,
+					    addrr->addr_len)) {
+					XFREE(MTYPE_ISIS_AREA_ADDR, addrr);
+					return NB_OK; /* silent fail */
+				}
+			}
+		}
+
+		/*Forget the systemID part of the address */
+		addrr->addr_len -= (ISIS_SYS_ID_LEN + ISIS_NSEL_LEN);
+		assert(area->area_addrs); /* to silence scan-build sillyness */
+		listnode_add(area->area_addrs, addrr);
+
+		/* only now we can safely generate our LSPs for this area */
+		if (listcount(area->area_addrs) > 0) {
+			if (area->is_type & IS_LEVEL_1)
+				lsp_generate(area, IS_LEVEL_1);
+			if (area->is_type & IS_LEVEL_2)
+				lsp_generate(area, IS_LEVEL_2);
+		}
+		break;
+	}
+
+	return NB_OK;
+}
+
+int isis_instance_area_address_destroy(struct nb_cb_destroy_args *args)
+{
+	struct iso_address addr, *addrp = NULL;
+	struct listnode *node;
+	uint8_t buff[255];
+	struct isis_area *area;
+	const char *net_title;
+	struct listnode *cnode;
+	struct isis_circuit *circuit;
+	int lvl;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	net_title = yang_dnode_get_string(args->dnode, NULL);
+	addr.addr_len = dotformat2buff(buff, net_title);
+	memcpy(addr.area_addr, buff, (int)addr.addr_len);
+	area = nb_running_get_entry(args->dnode, NULL, true);
+
+	for (ALL_LIST_ELEMENTS_RO(area->area_addrs, node, addrp)) {
+		if ((addrp->addr_len + ISIS_SYS_ID_LEN + 1) == addr.addr_len
+		    && !memcmp(addrp->area_addr, addr.area_addr, addr.addr_len))
+			break;
+	}
+	if (!addrp)
+		return NB_ERR_INCONSISTENCY;
+
+	listnode_delete(area->area_addrs, addrp);
+	XFREE(MTYPE_ISIS_AREA_ADDR, addrp);
+	/*
+	 * Last area address - reset the SystemID for this router
+	 */
+	if (listcount(area->area_addrs) == 0) {
+		for (ALL_LIST_ELEMENTS_RO(area->circuit_list, cnode, circuit))
+			for (lvl = IS_LEVEL_1; lvl <= IS_LEVEL_2; ++lvl) {
+				if (circuit->u.bc.is_dr[lvl - 1])
+					isis_dr_resign(circuit, lvl);
+			}
+		memset(area->isis->sysid, 0, ISIS_SYS_ID_LEN);
+		area->isis->sysid_set = 0;
+		if (IS_DEBUG_EVENTS)
+			zlog_debug("Router has no SystemID");
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/dynamic-hostname
+ */
+int isis_instance_dynamic_hostname_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	isis_area_dynhostname_set(area, yang_dnode_get_bool(args->dnode, NULL));
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/attach-send
+ */
+int isis_instance_attached_send_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	bool attached;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	attached = yang_dnode_get_bool(args->dnode, NULL);
+	isis_area_attached_bit_send_set(area, attached);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/attach-receive-ignore
+ */
+int isis_instance_attached_receive_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	bool attached;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	attached = yang_dnode_get_bool(args->dnode, NULL);
+	isis_area_attached_bit_receive_set(area, attached);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/attached
+ */
+int isis_instance_attached_modify(struct nb_cb_modify_args *args)
+{
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/overload/enabled
+ */
+int isis_instance_overload_enabled_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	bool overload;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	overload = yang_dnode_get_bool(args->dnode, NULL);
+	area->overload_configured = overload;
+
+	isis_area_overload_bit_set(area, overload);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/overload/on-startup
+ */
+int isis_instance_overload_on_startup_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	uint32_t overload_time;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	overload_time = yang_dnode_get_uint32(args->dnode, NULL);
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	isis_area_overload_on_startup_set(area, overload_time);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/advertise-high-metrics
+ */
+int isis_instance_advertise_high_metrics_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	bool advertise_high_metrics;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	advertise_high_metrics = yang_dnode_get_bool(args->dnode, NULL);
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	isis_area_advertise_high_metrics_set(area, advertise_high_metrics);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/metric-style
+ */
+int isis_instance_metric_style_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	bool old_metric, new_metric;
+	enum isis_metric_style metric_style =
+		yang_dnode_get_enum(args->dnode, NULL);
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	old_metric = (metric_style == ISIS_WIDE_METRIC) ? false : true;
+	new_metric = (metric_style == ISIS_NARROW_METRIC) ? false : true;
+	isis_area_metricstyle_set(area, old_metric, new_metric);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/purge-originator
+ */
+int isis_instance_purge_originator_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->purge_originator = yang_dnode_get_bool(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+
+/*
+ * XPath: /frr-isisd:isis/instance/admin-group-send-zero
+ */
+int isis_instance_admin_group_send_zero_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+	struct isis_area *area;
+	struct listnode *node;
+	struct flex_algo *fa;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->admin_group_send_zero = yang_dnode_get_bool(args->dnode, NULL);
+
+	if (area->admin_group_send_zero) {
+		for (ALL_LIST_ELEMENTS_RO(area->flex_algos->flex_algos, node,
+					  fa)) {
+			admin_group_allow_explicit_zero(
+				&fa->admin_group_exclude_any);
+			admin_group_allow_explicit_zero(
+				&fa->admin_group_include_any);
+			admin_group_allow_explicit_zero(
+				&fa->admin_group_include_all);
+		}
+	} else {
+		for (ALL_LIST_ELEMENTS_RO(area->flex_algos->flex_algos, node,
+					  fa)) {
+			admin_group_disallow_explicit_zero(
+				&fa->admin_group_exclude_any);
+			admin_group_disallow_explicit_zero(
+				&fa->admin_group_include_any);
+			admin_group_disallow_explicit_zero(
+				&fa->admin_group_include_all);
+		}
+	}
+
+	for (ALL_LIST_ELEMENTS_RO(area->circuit_list, node, circuit))
+		isis_link_params_update(circuit, circuit->interface);
+
+	lsp_regenerate_schedule(area, IS_LEVEL_1 | IS_LEVEL_2, 0);
+
+	return NB_OK;
+}
+
+
+/*
+ * XPath: /frr-isisd:isis/instance/asla-legacy-flag
+ */
+int isis_instance_asla_legacy_flag_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->asla_legacy_flag = yang_dnode_get_bool(args->dnode, NULL);
+	lsp_regenerate_schedule(area, IS_LEVEL_1 | IS_LEVEL_2, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/lsp/mtu
+ */
+int isis_instance_lsp_mtu_modify(struct nb_cb_modify_args *args)
+{
+	uint16_t lsp_mtu = yang_dnode_get_uint16(args->dnode, NULL);
+	struct isis_area *area;
+
+	switch (args->event) {
+	case NB_EV_VALIDATE:
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	case NB_EV_APPLY:
+		area = nb_running_get_entry(args->dnode, NULL, true);
+		isis_area_lsp_mtu_set(area, lsp_mtu);
+		break;
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/advertise-passive-only
+ */
+int isis_instance_advertise_passive_only_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	bool advertise_passive_only;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	advertise_passive_only = yang_dnode_get_bool(args->dnode, NULL);
+	area->advertise_passive_only = advertise_passive_only;
+
+	lsp_regenerate_schedule(area, IS_LEVEL_1 | IS_LEVEL_2, 1);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/lsp/timers/level-1/refresh-interval
+ */
+int isis_instance_lsp_refresh_interval_level_1_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	uint16_t refr_int;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	refr_int = yang_dnode_get_uint16(args->dnode, NULL);
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	isis_area_lsp_refresh_set(area, IS_LEVEL_1, refr_int);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/lsp/timers/level-2/refresh-interval
+ */
+int isis_instance_lsp_refresh_interval_level_2_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	uint16_t refr_int;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	refr_int = yang_dnode_get_uint16(args->dnode, NULL);
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	isis_area_lsp_refresh_set(area, IS_LEVEL_2, refr_int);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/lsp/timers/level-1/maximum-lifetime
+ */
+int isis_instance_lsp_maximum_lifetime_level_1_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	uint16_t max_lt;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	max_lt = yang_dnode_get_uint16(args->dnode, NULL);
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	isis_area_max_lsp_lifetime_set(area, IS_LEVEL_1, max_lt);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/lsp/timers/level-2/maximum-lifetime
+ */
+int isis_instance_lsp_maximum_lifetime_level_2_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	uint16_t max_lt;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	max_lt = yang_dnode_get_uint16(args->dnode, NULL);
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	isis_area_max_lsp_lifetime_set(area, IS_LEVEL_2, max_lt);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/lsp/timers/level-1/generation-interval
+ */
+int isis_instance_lsp_generation_interval_level_1_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	uint16_t gen_int;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	gen_int = yang_dnode_get_uint16(args->dnode, NULL);
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->lsp_gen_interval[0] = gen_int;
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/lsp/timers/level-2/generation-interval
+ */
+int isis_instance_lsp_generation_interval_level_2_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	uint16_t gen_int;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	gen_int = yang_dnode_get_uint16(args->dnode, NULL);
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->lsp_gen_interval[1] = gen_int;
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/spf/ietf-backoff-delay
+ */
+void ietf_backoff_delay_apply_finish(struct nb_cb_apply_finish_args *args)
+{
+	long init_delay = yang_dnode_get_uint16(args->dnode, "./init-delay");
+	long short_delay = yang_dnode_get_uint16(args->dnode, "./short-delay");
+	long long_delay = yang_dnode_get_uint16(args->dnode, "./long-delay");
+	long holddown = yang_dnode_get_uint16(args->dnode, "./hold-down");
+	long timetolearn =
+		yang_dnode_get_uint16(args->dnode, "./time-to-learn");
+	struct isis_area *area = nb_running_get_entry(args->dnode, NULL, true);
+	size_t bufsiz = strlen(area->area_tag) + sizeof("IS-IS  Lx");
+	char *buf = XCALLOC(MTYPE_TMP, bufsiz);
+
+	snprintf(buf, bufsiz, "IS-IS %s L1", area->area_tag);
+	spf_backoff_free(area->spf_delay_ietf[0]);
+	area->spf_delay_ietf[0] =
+		spf_backoff_new(master, buf, init_delay, short_delay,
+				long_delay, holddown, timetolearn);
+
+	snprintf(buf, bufsiz, "IS-IS %s L2", area->area_tag);
+	spf_backoff_free(area->spf_delay_ietf[1]);
+	area->spf_delay_ietf[1] =
+		spf_backoff_new(master, buf, init_delay, short_delay,
+				long_delay, holddown, timetolearn);
+
+	XFREE(MTYPE_TMP, buf);
+}
+
+int isis_instance_spf_ietf_backoff_delay_create(struct nb_cb_create_args *args)
+{
+	/* All the work is done in the apply_finish */
+	return NB_OK;
+}
+
+int isis_instance_spf_ietf_backoff_delay_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	spf_backoff_free(area->spf_delay_ietf[0]);
+	spf_backoff_free(area->spf_delay_ietf[1]);
+	area->spf_delay_ietf[0] = NULL;
+	area->spf_delay_ietf[1] = NULL;
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/spf/ietf-backoff-delay/init-delay
+ */
+int isis_instance_spf_ietf_backoff_delay_init_delay_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* All the work is done in the apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/spf/ietf-backoff-delay/short-delay
+ */
+int isis_instance_spf_ietf_backoff_delay_short_delay_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* All the work is done in the apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/spf/ietf-backoff-delay/long-delay
+ */
+int isis_instance_spf_ietf_backoff_delay_long_delay_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* All the work is done in the apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/spf/ietf-backoff-delay/hold-down
+ */
+int isis_instance_spf_ietf_backoff_delay_hold_down_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* All the work is done in the apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/spf/ietf-backoff-delay/time-to-learn
+ */
+int isis_instance_spf_ietf_backoff_delay_time_to_learn_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* All the work is done in the apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/spf/minimum-interval/level-1
+ */
+int isis_instance_spf_minimum_interval_level_1_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->min_spf_interval[0] = yang_dnode_get_uint16(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/spf/minimum-interval/level-2
+ */
+int isis_instance_spf_minimum_interval_level_2_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->min_spf_interval[1] = yang_dnode_get_uint16(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-isisd:isis/instance/spf/prefix-priorities/critical/access-list-name
+ */
+int isis_instance_spf_prefix_priorities_critical_access_list_name_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	const char *acl_name;
+	struct spf_prefix_priority_acl *ppa;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	acl_name = yang_dnode_get_string(args->dnode, NULL);
+
+	ppa = &area->spf_prefix_priorities[SPF_PREFIX_PRIO_CRITICAL];
+	XFREE(MTYPE_ISIS_ACL_NAME, ppa->name);
+	ppa->name = XSTRDUP(MTYPE_ISIS_ACL_NAME, acl_name);
+	ppa->list_v4 = access_list_lookup(AFI_IP, acl_name);
+	ppa->list_v6 = access_list_lookup(AFI_IP6, acl_name);
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+int isis_instance_spf_prefix_priorities_critical_access_list_name_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+	struct spf_prefix_priority_acl *ppa;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+
+	ppa = &area->spf_prefix_priorities[SPF_PREFIX_PRIO_CRITICAL];
+	XFREE(MTYPE_ISIS_ACL_NAME, ppa->name);
+	ppa->list_v4 = NULL;
+	ppa->list_v6 = NULL;
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/spf/prefix-priorities/high/access-list-name
+ */
+int isis_instance_spf_prefix_priorities_high_access_list_name_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	const char *acl_name;
+	struct spf_prefix_priority_acl *ppa;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	acl_name = yang_dnode_get_string(args->dnode, NULL);
+
+	ppa = &area->spf_prefix_priorities[SPF_PREFIX_PRIO_HIGH];
+	XFREE(MTYPE_ISIS_ACL_NAME, ppa->name);
+	ppa->name = XSTRDUP(MTYPE_ISIS_ACL_NAME, acl_name);
+	ppa->list_v4 = access_list_lookup(AFI_IP, acl_name);
+	ppa->list_v6 = access_list_lookup(AFI_IP6, acl_name);
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+int isis_instance_spf_prefix_priorities_high_access_list_name_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+	struct spf_prefix_priority_acl *ppa;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+
+	ppa = &area->spf_prefix_priorities[SPF_PREFIX_PRIO_HIGH];
+	XFREE(MTYPE_ISIS_ACL_NAME, ppa->name);
+	ppa->list_v4 = NULL;
+	ppa->list_v6 = NULL;
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/spf/prefix-priorities/medium/access-list-name
+ */
+int isis_instance_spf_prefix_priorities_medium_access_list_name_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	const char *acl_name;
+	struct spf_prefix_priority_acl *ppa;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	acl_name = yang_dnode_get_string(args->dnode, NULL);
+
+	ppa = &area->spf_prefix_priorities[SPF_PREFIX_PRIO_MEDIUM];
+	XFREE(MTYPE_ISIS_ACL_NAME, ppa->name);
+	ppa->name = XSTRDUP(MTYPE_ISIS_ACL_NAME, acl_name);
+	ppa->list_v4 = access_list_lookup(AFI_IP, acl_name);
+	ppa->list_v6 = access_list_lookup(AFI_IP6, acl_name);
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+int isis_instance_spf_prefix_priorities_medium_access_list_name_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+	struct spf_prefix_priority_acl *ppa;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+
+	ppa = &area->spf_prefix_priorities[SPF_PREFIX_PRIO_MEDIUM];
+	XFREE(MTYPE_ISIS_ACL_NAME, ppa->name);
+	ppa->list_v4 = NULL;
+	ppa->list_v6 = NULL;
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/area-password
+ */
+void area_password_apply_finish(struct nb_cb_apply_finish_args *args)
+{
+	const char *password = yang_dnode_get_string(args->dnode, "./password");
+	struct isis_area *area = nb_running_get_entry(args->dnode, NULL, true);
+	int pass_type = yang_dnode_get_enum(args->dnode, "./password-type");
+	uint8_t snp_auth =
+		yang_dnode_get_enum(args->dnode, "./authenticate-snp");
+
+	switch (pass_type) {
+	case ISIS_PASSWD_TYPE_CLEARTXT:
+		isis_area_passwd_cleartext_set(area, IS_LEVEL_1, password,
+					       snp_auth);
+		break;
+	case ISIS_PASSWD_TYPE_HMAC_MD5:
+		isis_area_passwd_hmac_md5_set(area, IS_LEVEL_1, password,
+					      snp_auth);
+		break;
+	}
+}
+
+int isis_instance_area_password_create(struct nb_cb_create_args *args)
+{
+	/* actual setting is done in apply_finish */
+	return NB_OK;
+}
+
+int isis_instance_area_password_destroy(struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	isis_area_passwd_unset(area, IS_LEVEL_1);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/area-password/password
+ */
+int isis_instance_area_password_password_modify(struct nb_cb_modify_args *args)
+{
+	/* actual setting is done in apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/area-password/password-type
+ */
+int isis_instance_area_password_password_type_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* actual setting is done in apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/area-password/authenticate-snp
+ */
+int isis_instance_area_password_authenticate_snp_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* actual setting is done in apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/domain-password
+ */
+void domain_password_apply_finish(struct nb_cb_apply_finish_args *args)
+{
+	const char *password = yang_dnode_get_string(args->dnode, "./password");
+	struct isis_area *area = nb_running_get_entry(args->dnode, NULL, true);
+	int pass_type = yang_dnode_get_enum(args->dnode, "./password-type");
+	uint8_t snp_auth =
+		yang_dnode_get_enum(args->dnode, "./authenticate-snp");
+
+	switch (pass_type) {
+	case ISIS_PASSWD_TYPE_CLEARTXT:
+		isis_area_passwd_cleartext_set(area, IS_LEVEL_2, password,
+					       snp_auth);
+		break;
+	case ISIS_PASSWD_TYPE_HMAC_MD5:
+		isis_area_passwd_hmac_md5_set(area, IS_LEVEL_2, password,
+					      snp_auth);
+		break;
+	}
+}
+
+int isis_instance_domain_password_create(struct nb_cb_create_args *args)
+{
+	/* actual setting is done in apply_finish */
+	return NB_OK;
+}
+
+int isis_instance_domain_password_destroy(struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	isis_area_passwd_unset(area, IS_LEVEL_2);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/domain-password/password
+ */
+int isis_instance_domain_password_password_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* actual setting is done in apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/domain-password/password-type
+ */
+int isis_instance_domain_password_password_type_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* actual setting is done in apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/domain-password/authenticate-snp
+ */
+int isis_instance_domain_password_authenticate_snp_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* actual setting is done in apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/default-information-originate/ipv4
+ */
+void default_info_origin_apply_finish(const struct lyd_node *dnode, int family)
+{
+	int originate_type = DEFAULT_ORIGINATE;
+	unsigned long metric = 0;
+	const char *routemap = NULL;
+	struct isis_area *area = nb_running_get_entry(dnode, NULL, true);
+	int level = yang_dnode_get_enum(dnode, "./level");
+
+	if (yang_dnode_get_bool(dnode, "./always")) {
+		originate_type = DEFAULT_ORIGINATE_ALWAYS;
+	} else if (family == AF_INET6) {
+		zlog_warn(
+			"%s: Zebra doesn't implement default-originate for IPv6 yet, so use with care or use default-originate always.",
+			__func__);
+	}
+
+	if (yang_dnode_exists(dnode, "./metric"))
+		metric = yang_dnode_get_uint32(dnode, "./metric");
+	if (yang_dnode_exists(dnode, "./route-map"))
+		routemap = yang_dnode_get_string(dnode, "./route-map");
+
+	isis_redist_set(area, level, family, DEFAULT_ROUTE, metric, routemap,
+			originate_type, 0);
+}
+
+void default_info_origin_ipv4_apply_finish(struct nb_cb_apply_finish_args *args)
+{
+	default_info_origin_apply_finish(args->dnode, AF_INET);
+}
+
+void default_info_origin_ipv6_apply_finish(struct nb_cb_apply_finish_args *args)
+{
+	default_info_origin_apply_finish(args->dnode, AF_INET6);
+}
+
+int isis_instance_default_information_originate_ipv4_create(
+	struct nb_cb_create_args *args)
+{
+	/* It's all done by default_info_origin_apply_finish */
+	return NB_OK;
+}
+
+int isis_instance_default_information_originate_ipv4_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+	int level;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	level = yang_dnode_get_enum(args->dnode, "./level");
+	isis_redist_unset(area, level, AF_INET, DEFAULT_ROUTE, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/default-information-originate/ipv4/always
+ */
+int isis_instance_default_information_originate_ipv4_always_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* It's all done by default_info_origin_apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/default-information-originate/ipv4/route-map
+ */
+int isis_instance_default_information_originate_ipv4_route_map_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* It's all done by default_info_origin_apply_finish */
+	return NB_OK;
+}
+
+int isis_instance_default_information_originate_ipv4_route_map_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	/* It's all done by default_info_origin_apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/default-information-originate/ipv4/metric
+ */
+int isis_instance_default_information_originate_ipv4_metric_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* It's all done by default_info_origin_apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/default-information-originate/ipv6
+ */
+int isis_instance_default_information_originate_ipv6_create(
+	struct nb_cb_create_args *args)
+{
+	/* It's all done by default_info_origin_apply_finish */
+	return NB_OK;
+}
+
+int isis_instance_default_information_originate_ipv6_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+	int level;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	level = yang_dnode_get_enum(args->dnode, "./level");
+	isis_redist_unset(area, level, AF_INET6, DEFAULT_ROUTE, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/default-information-originate/ipv6/always
+ */
+int isis_instance_default_information_originate_ipv6_always_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* It's all done by default_info_origin_apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/default-information-originate/ipv6/route-map
+ */
+int isis_instance_default_information_originate_ipv6_route_map_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* It's all done by default_info_origin_apply_finish */
+	return NB_OK;
+}
+
+int isis_instance_default_information_originate_ipv6_route_map_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	/* It's all done by default_info_origin_apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/default-information-originate/ipv6/metric
+ */
+int isis_instance_default_information_originate_ipv6_metric_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* It's all done by default_info_origin_apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/redistribute/ipv4
+ */
+void redistribute_apply_finish(const struct lyd_node *dnode, int family)
+{
+	assert(family == AF_INET || family == AF_INET6);
+	int type, level;
+	unsigned long metric = 0;
+	const char *routemap = NULL;
+	struct isis_area *area;
+
+	type = yang_dnode_get_enum(dnode, "./protocol");
+	level = yang_dnode_get_enum(dnode, "./level");
+	area = nb_running_get_entry(dnode, NULL, true);
+
+	if (yang_dnode_exists(dnode, "./metric"))
+		metric = yang_dnode_get_uint32(dnode, "./metric");
+	if (yang_dnode_exists(dnode, "./route-map"))
+		routemap = yang_dnode_get_string(dnode, "./route-map");
+
+	isis_redist_set(area, level, family, type, metric, routemap, 0, 0);
+}
+
+void redistribute_ipv4_apply_finish(struct nb_cb_apply_finish_args *args)
+{
+	redistribute_apply_finish(args->dnode, AF_INET);
+}
+
+void redistribute_ipv6_apply_finish(struct nb_cb_apply_finish_args *args)
+{
+	redistribute_apply_finish(args->dnode, AF_INET6);
+}
+
+int isis_instance_redistribute_ipv4_create(struct nb_cb_create_args *args)
+{
+	/* It's all done by redistribute_apply_finish */
+	return NB_OK;
+}
+
+int isis_instance_redistribute_ipv4_destroy(struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+	int level, type;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	level = yang_dnode_get_enum(args->dnode, "./level");
+	type = yang_dnode_get_enum(args->dnode, "./protocol");
+	isis_redist_unset(area, level, AF_INET, type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/redistribute/ipv4/route-map
+ * XPath: /frr-isisd:isis/instance/redistribute/ipv4/table/route-map
+ */
+int isis_instance_redistribute_ipv4_route_map_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* It's all done by redistribute_apply_finish */
+	return NB_OK;
+}
+
+int isis_instance_redistribute_ipv4_route_map_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	/* It's all done by redistribute_apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/redistribute/ipv4/metric
+ * XPath: /frr-isisd:isis/instance/redistribute/ipv4/table/metric
+ */
+int isis_instance_redistribute_ipv4_metric_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* It's all done by redistribute_apply_finish */
+	return NB_OK;
+}
+
+int isis_instance_redistribute_ipv4_metric_destroy(struct nb_cb_destroy_args *args)
+{
+	/* It's all done by redistribute_apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/redistribute/ipv4/table
+ */
+int isis_instance_redistribute_ipv4_table_create(struct nb_cb_create_args *args)
+{
+	uint16_t table;
+	int type, level;
+	unsigned long metric = 0;
+	const char *routemap = NULL;
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	type = yang_dnode_get_enum(args->dnode, "../protocol");
+	level = yang_dnode_get_enum(args->dnode, "../level");
+	area = nb_running_get_entry(args->dnode, "../.", true);
+
+	if (yang_dnode_exists(args->dnode, "./metric"))
+		metric = yang_dnode_get_uint32(args->dnode, "./metric");
+	if (yang_dnode_exists(args->dnode, "./route-map"))
+		routemap = yang_dnode_get_string(args->dnode, "./route-map");
+
+	table = yang_dnode_get_uint16(args->dnode, "./table");
+	isis_redist_set(area, level, AF_INET, type, metric, routemap, 0, table);
+
+	return NB_OK;
+}
+int isis_instance_redistribute_ipv4_table_destroy(struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+	int level, type;
+	uint16_t table;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, "../.", true);
+	level = yang_dnode_get_enum(args->dnode, "../level");
+	type = yang_dnode_get_enum(args->dnode, "../protocol");
+	table = yang_dnode_get_uint16(args->dnode, "./table");
+	isis_redist_unset(area, level, AF_INET, type, table);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/redistribute/ipv6
+ */
+int isis_instance_redistribute_ipv6_create(struct nb_cb_create_args *args)
+{
+	/* It's all done by redistribute_apply_finish */
+	return NB_OK;
+}
+
+int isis_instance_redistribute_ipv6_destroy(struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+	int level, type;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	level = yang_dnode_get_enum(args->dnode, "./level");
+	type = yang_dnode_get_enum(args->dnode, "./protocol");
+	isis_redist_unset(area, level, AF_INET6, type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/redistribute/ipv6/route-map
+ */
+int isis_instance_redistribute_ipv6_route_map_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* It's all done by redistribute_apply_finish */
+	return NB_OK;
+}
+
+int isis_instance_redistribute_ipv6_route_map_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	/* It's all done by redistribute_apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/redistribute/ipv6/metric
+ */
+int isis_instance_redistribute_ipv6_metric_modify(
+	struct nb_cb_modify_args *args)
+{
+	/* It's all done by redistribute_apply_finish */
+	return NB_OK;
+}
+
+int isis_instance_redistribute_ipv6_metric_destroy(struct nb_cb_destroy_args *args)
+{
+	/* It's all done by redistribute_apply_finish */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/redistribute/ipv6/table
+ */
+int isis_instance_redistribute_ipv6_table_create(struct nb_cb_create_args *args)
+{
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	/* TODO */
+	return NB_OK;
+}
+
+int isis_instance_redistribute_ipv6_table_destroy(struct nb_cb_destroy_args *args)
+{
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	/* TODO */
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/multi-topology/ipv4-multicast
+ */
+static int isis_multi_topology_common(enum nb_event event,
+				      const struct lyd_node *dnode,
+				      char *errmsg, size_t errmsg_len,
+				      const char *topology, bool create)
+{
+	struct isis_area *area;
+	struct isis_area_mt_setting *setting;
+	uint16_t mtid = isis_str2mtid(topology);
+
+	switch (event) {
+	case NB_EV_VALIDATE:
+		if (mtid == (uint16_t)-1) {
+			snprintf(errmsg, errmsg_len, "Unknown topology %s",
+				 topology);
+			return NB_ERR_VALIDATION;
+		}
+		break;
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	case NB_EV_APPLY:
+		area = nb_running_get_entry(dnode, NULL, true);
+		setting = area_get_mt_setting(area, mtid);
+		setting->enabled = create;
+		lsp_regenerate_schedule(area, IS_LEVEL_1 | IS_LEVEL_2, 0);
+		break;
+	}
+
+	return NB_OK;
+}
+
+static int isis_multi_topology_overload_common(enum nb_event event,
+					       const struct lyd_node *dnode,
+					       const char *topology)
+{
+	struct isis_area *area;
+	struct isis_area_mt_setting *setting;
+	uint16_t mtid = isis_str2mtid(topology);
+
+	/* validation is done in isis_multi_topology_common */
+	if (event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(dnode, NULL, true);
+	setting = area_get_mt_setting(area, mtid);
+	setting->overload = yang_dnode_get_bool(dnode, NULL);
+	if (setting->enabled)
+		lsp_regenerate_schedule(area, IS_LEVEL_1 | IS_LEVEL_2, 0);
+
+	return NB_OK;
+}
+
+int isis_instance_multi_topology_ipv4_multicast_create(
+	struct nb_cb_create_args *args)
+{
+	return isis_multi_topology_common(args->event, args->dnode,
+					  args->errmsg, args->errmsg_len,
+					  "ipv4-multicast", true);
+}
+
+int isis_instance_multi_topology_ipv4_multicast_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	return isis_multi_topology_common(args->event, args->dnode,
+					  args->errmsg, args->errmsg_len,
+					  "ipv4-multicast", false);
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/multi-topology/ipv4-multicast/overload
+ */
+int isis_instance_multi_topology_ipv4_multicast_overload_modify(
+	struct nb_cb_modify_args *args)
+{
+	return isis_multi_topology_overload_common(args->event, args->dnode,
+						   "ipv4-multicast");
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/multi-topology/ipv4-management
+ */
+int isis_instance_multi_topology_ipv4_management_create(
+	struct nb_cb_create_args *args)
+{
+	return isis_multi_topology_common(args->event, args->dnode,
+					  args->errmsg, args->errmsg_len,
+					  "ipv4-mgmt", true);
+}
+
+int isis_instance_multi_topology_ipv4_management_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	return isis_multi_topology_common(args->event, args->dnode,
+					  args->errmsg, args->errmsg_len,
+					  "ipv4-mgmt", false);
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/multi-topology/ipv4-management/overload
+ */
+int isis_instance_multi_topology_ipv4_management_overload_modify(
+	struct nb_cb_modify_args *args)
+{
+	return isis_multi_topology_overload_common(args->event, args->dnode,
+						   "ipv4-mgmt");
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/multi-topology/ipv6-unicast
+ */
+int isis_instance_multi_topology_ipv6_unicast_create(
+	struct nb_cb_create_args *args)
+{
+	return isis_multi_topology_common(args->event, args->dnode,
+					  args->errmsg, args->errmsg_len,
+					  "ipv6-unicast", true);
+}
+
+int isis_instance_multi_topology_ipv6_unicast_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	return isis_multi_topology_common(args->event, args->dnode,
+					  args->errmsg, args->errmsg_len,
+					  "ipv6-unicast", false);
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/multi-topology/ipv6-unicast/overload
+ */
+int isis_instance_multi_topology_ipv6_unicast_overload_modify(
+	struct nb_cb_modify_args *args)
+{
+	return isis_multi_topology_overload_common(args->event, args->dnode,
+						   "ipv6-unicast");
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/multi-topology/ipv6-multicast
+ */
+int isis_instance_multi_topology_ipv6_multicast_create(
+	struct nb_cb_create_args *args)
+{
+	return isis_multi_topology_common(args->event, args->dnode,
+					  args->errmsg, args->errmsg_len,
+					  "ipv6-multicast", true);
+}
+
+int isis_instance_multi_topology_ipv6_multicast_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	return isis_multi_topology_common(args->event, args->dnode,
+					  args->errmsg, args->errmsg_len,
+					  "ipv6-multicast", false);
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/multi-topology/ipv6-multicast/overload
+ */
+int isis_instance_multi_topology_ipv6_multicast_overload_modify(
+	struct nb_cb_modify_args *args)
+{
+	return isis_multi_topology_overload_common(args->event, args->dnode,
+						   "ipv6-multicast");
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/multi-topology/ipv6-management
+ */
+int isis_instance_multi_topology_ipv6_management_create(
+	struct nb_cb_create_args *args)
+{
+	return isis_multi_topology_common(args->event, args->dnode,
+					  args->errmsg, args->errmsg_len,
+					  "ipv6-mgmt", true);
+}
+
+int isis_instance_multi_topology_ipv6_management_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	return isis_multi_topology_common(args->event, args->dnode,
+					  args->errmsg, args->errmsg_len,
+					  "ipv6-mgmt", false);
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/multi-topology/ipv6-management/overload
+ */
+int isis_instance_multi_topology_ipv6_management_overload_modify(
+	struct nb_cb_modify_args *args)
+{
+	return isis_multi_topology_overload_common(args->event, args->dnode,
+						   "ipv6-mgmt");
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/multi-topology/ipv6-dstsrc
+ */
+int isis_instance_multi_topology_ipv6_dstsrc_create(
+	struct nb_cb_create_args *args)
+{
+	return isis_multi_topology_common(args->event, args->dnode,
+					  args->errmsg, args->errmsg_len,
+					  "ipv6-dstsrc", true);
+}
+
+int isis_instance_multi_topology_ipv6_dstsrc_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	return isis_multi_topology_common(args->event, args->dnode,
+					  args->errmsg, args->errmsg_len,
+					  "ipv6-dstsrc", false);
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/multi-topology/ipv6-dstsrc/overload
+ */
+int isis_instance_multi_topology_ipv6_dstsrc_overload_modify(
+	struct nb_cb_modify_args *args)
+{
+	return isis_multi_topology_overload_common(args->event, args->dnode,
+						   "ipv6-dstsrc");
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/fast-reroute/level-1/lfa/load-sharing
+ */
+int isis_instance_fast_reroute_level_1_lfa_load_sharing_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->lfa_load_sharing[0] = yang_dnode_get_bool(args->dnode, NULL);
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/fast-reroute/level-1/lfa/priority-limit
+ */
+int isis_instance_fast_reroute_level_1_lfa_priority_limit_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->lfa_priority_limit[0] = yang_dnode_get_enum(args->dnode, NULL);
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+int isis_instance_fast_reroute_level_1_lfa_priority_limit_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->lfa_priority_limit[0] = SPF_PREFIX_PRIO_LOW;
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/fast-reroute/level-1/lfa/tiebreaker
+ */
+int isis_instance_fast_reroute_level_1_lfa_tiebreaker_create(
+	struct nb_cb_create_args *args)
+{
+	struct isis_area *area;
+	uint8_t index;
+	enum lfa_tiebreaker_type type;
+	struct lfa_tiebreaker *tie_b;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	index = yang_dnode_get_uint8(args->dnode, "./index");
+	type = yang_dnode_get_enum(args->dnode, "./type");
+
+	tie_b = isis_lfa_tiebreaker_add(area, ISIS_LEVEL1, index, type);
+	nb_running_set_entry(args->dnode, tie_b);
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+int isis_instance_fast_reroute_level_1_lfa_tiebreaker_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct lfa_tiebreaker *tie_b;
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	tie_b = nb_running_unset_entry(args->dnode);
+	area = tie_b->area;
+	isis_lfa_tiebreaker_delete(area, ISIS_LEVEL1, tie_b);
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/fast-reroute/level-1/lfa/tiebreaker/type
+ */
+int isis_instance_fast_reroute_level_1_lfa_tiebreaker_type_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct lfa_tiebreaker *tie_b;
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	tie_b = nb_running_get_entry(args->dnode, NULL, true);
+	area = tie_b->area;
+	tie_b->type = yang_dnode_get_enum(args->dnode, NULL);
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/fast-reroute/level-1/remote-lfa/prefix-list
+ */
+int isis_instance_fast_reroute_level_1_remote_lfa_prefix_list_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	const char *plist_name;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	plist_name = yang_dnode_get_string(args->dnode, NULL);
+
+	area->rlfa_plist_name[0] = XSTRDUP(MTYPE_ISIS_PLIST_NAME, plist_name);
+	area->rlfa_plist[0] = prefix_list_lookup(AFI_IP, plist_name);
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+int isis_instance_fast_reroute_level_1_remote_lfa_prefix_list_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+
+	XFREE(MTYPE_ISIS_PLIST_NAME, area->rlfa_plist_name[0]);
+	area->rlfa_plist[0] = NULL;
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/fast-reroute/level-2/lfa/load-sharing
+ */
+int isis_instance_fast_reroute_level_2_lfa_load_sharing_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->lfa_load_sharing[1] = yang_dnode_get_bool(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/fast-reroute/level-2/lfa/priority-limit
+ */
+int isis_instance_fast_reroute_level_2_lfa_priority_limit_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->lfa_priority_limit[1] = yang_dnode_get_enum(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+int isis_instance_fast_reroute_level_2_lfa_priority_limit_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->lfa_priority_limit[1] = SPF_PREFIX_PRIO_LOW;
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/fast-reroute/level-2/lfa/tiebreaker
+ */
+int isis_instance_fast_reroute_level_2_lfa_tiebreaker_create(
+	struct nb_cb_create_args *args)
+{
+	struct isis_area *area;
+	uint8_t index;
+	enum lfa_tiebreaker_type type;
+	struct lfa_tiebreaker *tie_b;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	index = yang_dnode_get_uint8(args->dnode, "./index");
+	type = yang_dnode_get_enum(args->dnode, "./type");
+
+	tie_b = isis_lfa_tiebreaker_add(area, ISIS_LEVEL2, index, type);
+	nb_running_set_entry(args->dnode, tie_b);
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+int isis_instance_fast_reroute_level_2_lfa_tiebreaker_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct lfa_tiebreaker *tie_b;
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	tie_b = nb_running_unset_entry(args->dnode);
+	area = tie_b->area;
+	isis_lfa_tiebreaker_delete(area, ISIS_LEVEL2, tie_b);
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/fast-reroute/level-2/lfa/tiebreaker/type
+ */
+int isis_instance_fast_reroute_level_2_lfa_tiebreaker_type_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct lfa_tiebreaker *tie_b;
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	tie_b = nb_running_get_entry(args->dnode, NULL, true);
+	area = tie_b->area;
+	tie_b->type = yang_dnode_get_enum(args->dnode, NULL);
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/fast-reroute/level-2/remote-lfa/prefix-list
+ */
+int isis_instance_fast_reroute_level_2_remote_lfa_prefix_list_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	const char *plist_name;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	plist_name = yang_dnode_get_string(args->dnode, NULL);
+
+	area->rlfa_plist_name[1] = XSTRDUP(MTYPE_ISIS_PLIST_NAME, plist_name);
+	area->rlfa_plist[1] = prefix_list_lookup(AFI_IP, plist_name);
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+int isis_instance_fast_reroute_level_2_remote_lfa_prefix_list_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+
+	XFREE(MTYPE_ISIS_PLIST_NAME, area->rlfa_plist_name[1]);
+	area->rlfa_plist[1] = NULL;
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/log-adjacency-changes
+ */
+int isis_instance_log_adjacency_changes_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	bool log = yang_dnode_get_bool(args->dnode, NULL);
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->log_adj_changes = log ? 1 : 0;
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/log-pdu-drops
+ */
+int isis_instance_log_pdu_drops_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	bool log = yang_dnode_get_bool(args->dnode, NULL);
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->log_pdu_drops = log ? 1 : 0;
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/mpls-te
+ */
+int isis_instance_mpls_te_create(struct nb_cb_create_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	isis_mpls_te_create(area);
+
+	/* Reoriginate STD_TE & GMPLS circuits */
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+int isis_instance_mpls_te_destroy(struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	if (!IS_MPLS_TE(area->mta))
+		return NB_OK;
+
+	isis_mpls_te_disable(area);
+
+	/* Reoriginate STD_TE & GMPLS circuits */
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	zlog_debug("ISIS-TE(%s): Disabled MPLS Traffic Engineering",
+		   area->area_tag);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/mpls-te/router-address
+ */
+int isis_instance_mpls_te_router_address_modify(struct nb_cb_modify_args *args)
+{
+	struct in_addr value;
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	/* only proceed if MPLS-TE is enabled */
+	if (!IS_MPLS_TE(area->mta))
+		return NB_OK;
+
+	/* Update Area Router ID */
+	yang_dnode_get_ipv4(&value, args->dnode, NULL);
+	area->mta->router_id.s_addr = value.s_addr;
+
+	/* And re-schedule LSP update */
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+int isis_instance_mpls_te_router_address_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	/* only proceed if MPLS-TE is enabled */
+	if (!IS_MPLS_TE(area->mta))
+		return NB_OK;
+
+	/* Reset Area Router ID */
+	area->mta->router_id.s_addr = INADDR_ANY;
+
+	/* And re-schedule LSP update */
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/mpls-te/router-address-v6
+ */
+int isis_instance_mpls_te_router_address_ipv6_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct in6_addr value;
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	/* only proceed if MPLS-TE is enabled */
+	if (!IS_MPLS_TE(area->mta))
+		return NB_OK;
+
+	yang_dnode_get_ipv6(&value, args->dnode, NULL);
+	/* Update Area IPv6 Router ID if different */
+	if (!IPV6_ADDR_SAME(&area->mta->router_id_ipv6, &value)) {
+		IPV6_ADDR_COPY(&area->mta->router_id_ipv6, &value);
+
+		/* And re-schedule LSP update */
+		lsp_regenerate_schedule(area, area->is_type, 0);
+	}
+
+	return NB_OK;
+}
+
+int isis_instance_mpls_te_router_address_ipv6_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	/* only proceed if MPLS-TE is enabled */
+	if (!IS_MPLS_TE(area->mta))
+		return NB_OK;
+
+	/* Reset Area Router ID */
+	IPV6_ADDR_COPY(&area->mta->router_id_ipv6, &in6addr_any);
+
+	/* And re-schedule LSP update */
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/mpls-te/export
+ */
+int isis_instance_mpls_te_export_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	/* only proceed if MPLS-TE is enabled */
+	if (!IS_MPLS_TE(area->mta))
+		return NB_OK;
+
+	area->mta->export = yang_dnode_get_bool(args->dnode, NULL);
+	if (area->mta->export) {
+		if (IS_DEBUG_EVENTS)
+			zlog_debug("MPLS-TE: Enabled Link State export");
+		if (isis_zebra_ls_register(true) != 0)
+			zlog_warn("Unable to register Link State");
+	} else {
+		if (IS_DEBUG_EVENTS)
+			zlog_debug("MPLS-TE: Disable Link State export");
+		if (isis_zebra_ls_register(false) != 0)
+			zlog_warn("Unable to register Link State");
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/segment-routing/enabled
+ */
+int isis_instance_segment_routing_enabled_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->srdb.config.enabled = yang_dnode_get_bool(args->dnode, NULL);
+
+	if (area->srdb.config.enabled) {
+		if (IS_DEBUG_EVENTS)
+			zlog_debug("SR: Segment Routing: OFF -> ON");
+
+		isis_sr_start(area);
+	} else {
+		if (IS_DEBUG_EVENTS)
+			zlog_debug("SR: Segment Routing: ON -> OFF");
+
+		isis_sr_stop(area);
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/segment-routing/label-blocks
+ */
+int isis_instance_segment_routing_label_blocks_pre_validate(
+	struct nb_cb_pre_validate_args *args)
+{
+	uint32_t srgb_lbound;
+	uint32_t srgb_ubound;
+	uint32_t srlb_lbound;
+	uint32_t srlb_ubound;
+
+	srgb_lbound = yang_dnode_get_uint32(args->dnode, "./srgb/lower-bound");
+	srgb_ubound = yang_dnode_get_uint32(args->dnode, "./srgb/upper-bound");
+	srlb_lbound = yang_dnode_get_uint32(args->dnode, "./srlb/lower-bound");
+	srlb_ubound = yang_dnode_get_uint32(args->dnode, "./srlb/upper-bound");
+
+	/* Check that the block size does not exceed 65535 */
+	if ((srgb_ubound - srgb_lbound + 1) > 65535) {
+		snprintf(
+			args->errmsg, args->errmsg_len,
+			"New SR Global Block (%u/%u) exceed the limit of 65535",
+			srgb_lbound, srgb_ubound);
+		return NB_ERR_VALIDATION;
+	}
+	if ((srlb_ubound - srlb_lbound + 1) > 65535) {
+		snprintf(args->errmsg, args->errmsg_len,
+			 "New SR Local Block (%u/%u) exceed the limit of 65535",
+			 srlb_lbound, srlb_ubound);
+		return NB_ERR_VALIDATION;
+	}
+
+	/* Validate SRGB against SRLB */
+	if (!((srgb_ubound < srlb_lbound) || (srgb_lbound > srlb_ubound))) {
+		snprintf(
+			args->errmsg, args->errmsg_len,
+			"SR Global Block (%u/%u) conflicts with Local Block (%u/%u)",
+			srgb_lbound, srgb_ubound, srlb_lbound, srlb_ubound);
+		return NB_ERR_VALIDATION;
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/segment-routing/label-blocks/srgb
+ */
+
+void isis_instance_segment_routing_srgb_apply_finish(
+	struct nb_cb_apply_finish_args *args)
+{
+	struct isis_area *area;
+	uint32_t lower_bound, upper_bound;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	lower_bound = yang_dnode_get_uint32(args->dnode, "./lower-bound");
+	upper_bound = yang_dnode_get_uint32(args->dnode, "./upper-bound");
+
+	isis_sr_cfg_srgb_update(area, lower_bound, upper_bound);
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/segment-routing/label-blocks/srgb/lower-bound
+ */
+int isis_instance_segment_routing_srgb_lower_bound_modify(
+	struct nb_cb_modify_args *args)
+{
+	uint32_t lower_bound = yang_dnode_get_uint32(args->dnode, NULL);
+
+	switch (args->event) {
+	case NB_EV_VALIDATE:
+		if (!IS_MPLS_UNRESERVED_LABEL(lower_bound)) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "Invalid SRGB lower bound: %u", lower_bound);
+			return NB_ERR_VALIDATION;
+		}
+		break;
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+	case NB_EV_APPLY:
+		break;
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/segment-routing/label-blocks/srgb/upper-bound
+ */
+int isis_instance_segment_routing_srgb_upper_bound_modify(
+	struct nb_cb_modify_args *args)
+{
+	uint32_t upper_bound = yang_dnode_get_uint32(args->dnode, NULL);
+
+	switch (args->event) {
+	case NB_EV_VALIDATE:
+		if (!IS_MPLS_UNRESERVED_LABEL(upper_bound)) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "Invalid SRGB upper bound: %u", upper_bound);
+			return NB_ERR_VALIDATION;
+		}
+		break;
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+	case NB_EV_APPLY:
+		break;
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/segment-routing/label-blocks/srlb
+ */
+void isis_instance_segment_routing_srlb_apply_finish(
+	struct nb_cb_apply_finish_args *args)
+{
+	struct isis_area *area;
+	uint32_t lower_bound, upper_bound;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	lower_bound = yang_dnode_get_uint32(args->dnode, "./lower-bound");
+	upper_bound = yang_dnode_get_uint32(args->dnode, "./upper-bound");
+
+	isis_sr_cfg_srlb_update(area, lower_bound, upper_bound);
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/segment-routing/label-blocks/srlb/lower-bound
+ */
+int isis_instance_segment_routing_srlb_lower_bound_modify(
+	struct nb_cb_modify_args *args)
+{
+	uint32_t lower_bound = yang_dnode_get_uint32(args->dnode, NULL);
+
+	switch (args->event) {
+	case NB_EV_VALIDATE:
+		if (!IS_MPLS_UNRESERVED_LABEL(lower_bound)) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "Invalid SRLB lower bound: %u", lower_bound);
+			return NB_ERR_VALIDATION;
+		}
+		break;
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+	case NB_EV_APPLY:
+		break;
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/segment-routing/label-blocks/srlb/upper-bound
+ */
+int isis_instance_segment_routing_srlb_upper_bound_modify(
+	struct nb_cb_modify_args *args)
+{
+	uint32_t upper_bound = yang_dnode_get_uint32(args->dnode, NULL);
+
+	switch (args->event) {
+	case NB_EV_VALIDATE:
+		if (!IS_MPLS_UNRESERVED_LABEL(upper_bound)) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "Invalid SRLB upper bound: %u", upper_bound);
+			return NB_ERR_VALIDATION;
+		}
+		break;
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+	case NB_EV_APPLY:
+		break;
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/segment-routing/msd/node-msd
+ */
+int isis_instance_segment_routing_msd_node_msd_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->srdb.config.msd = yang_dnode_get_uint8(args->dnode, NULL);
+
+	/* Update and regenerate LSP */
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+int isis_instance_segment_routing_msd_node_msd_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->srdb.config.msd = 0;
+
+	/* Update and regenerate LSP */
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/segment-routing/prefix-sid-map/prefix-sid
+ */
+int isis_instance_segment_routing_prefix_sid_map_prefix_sid_create(
+	struct nb_cb_create_args *args)
+{
+	struct isis_area *area;
+	struct prefix prefix;
+	struct sr_prefix_cfg *pcfg;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	yang_dnode_get_prefix(&prefix, args->dnode, "./prefix");
+
+	pcfg = isis_sr_cfg_prefix_add(area, &prefix, SR_ALGORITHM_SPF);
+	nb_running_set_entry(args->dnode, pcfg);
+
+	return NB_OK;
+}
+
+int isis_instance_segment_routing_prefix_sid_map_prefix_sid_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct sr_prefix_cfg *pcfg;
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	pcfg = nb_running_unset_entry(args->dnode);
+	area = pcfg->area;
+	isis_sr_cfg_prefix_del(pcfg);
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+int isis_instance_segment_routing_prefix_sid_map_prefix_sid_pre_validate(
+	struct nb_cb_pre_validate_args *args)
+{
+	const struct lyd_node *area_dnode;
+	struct isis_area *area;
+	struct prefix prefix;
+	uint32_t srgb_lbound;
+	uint32_t srgb_ubound;
+	uint32_t srgb_range;
+	uint32_t sid;
+	enum sr_sid_value_type sid_type;
+	struct isis_prefix_sid psid = {};
+
+	yang_dnode_get_prefix(&prefix, args->dnode, "./prefix");
+	srgb_lbound = yang_dnode_get_uint32(
+		args->dnode, "../../label-blocks/srgb/lower-bound");
+	srgb_ubound = yang_dnode_get_uint32(
+		args->dnode, "../../label-blocks/srgb/upper-bound");
+	sid = yang_dnode_get_uint32(args->dnode, "./sid-value");
+	sid_type = yang_dnode_get_enum(args->dnode, "./sid-value-type");
+
+	/* Check for invalid indexes/labels. */
+	srgb_range = srgb_ubound - srgb_lbound + 1;
+	psid.value = sid;
+	switch (sid_type) {
+	case SR_SID_VALUE_TYPE_INDEX:
+		if (sid >= srgb_range) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "SID index %u falls outside local SRGB range",
+				 sid);
+			return NB_ERR_VALIDATION;
+		}
+		break;
+	case SR_SID_VALUE_TYPE_ABSOLUTE:
+		if (!IS_MPLS_UNRESERVED_LABEL(sid)) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "Invalid absolute SID %u", sid);
+			return NB_ERR_VALIDATION;
+		}
+		SET_FLAG(psid.flags, ISIS_PREFIX_SID_VALUE);
+		SET_FLAG(psid.flags, ISIS_PREFIX_SID_LOCAL);
+		break;
+	}
+
+	/* Check for Prefix-SID collisions. */
+	area_dnode = yang_dnode_get_parent(args->dnode, "instance");
+	area = nb_running_get_entry(area_dnode, NULL, false);
+	if (area) {
+		for (int tree = SPFTREE_IPV4; tree < SPFTREE_COUNT; tree++) {
+			for (int level = ISIS_LEVEL1; level <= ISIS_LEVEL2;
+			     level++) {
+				struct isis_spftree *spftree;
+				struct isis_vertex *vertex_psid;
+
+				if (!(area->is_type & level))
+					continue;
+				spftree = area->spftree[tree][level - 1];
+				if (!spftree)
+					continue;
+
+				vertex_psid = isis_spf_prefix_sid_lookup(
+					spftree, &psid);
+				if (vertex_psid
+				    && !prefix_same(&vertex_psid->N.ip.p.dest,
+						    &prefix)) {
+					snprintfrr(
+						args->errmsg, args->errmsg_len,
+						"Prefix-SID collision detected, SID %s %u is already in use by prefix %pFX (L%u)",
+						CHECK_FLAG(
+							psid.flags,
+							ISIS_PREFIX_SID_VALUE)
+							? "label"
+							: "index",
+						psid.value,
+						&vertex_psid->N.ip.p.dest,
+						level);
+					return NB_ERR_VALIDATION;
+				}
+			}
+		}
+	}
+
+	return NB_OK;
+}
+
+void isis_instance_segment_routing_prefix_sid_map_prefix_sid_apply_finish(
+	struct nb_cb_apply_finish_args *args)
+{
+	struct sr_prefix_cfg *pcfg;
+	struct isis_area *area;
+
+	pcfg = nb_running_get_entry(args->dnode, NULL, true);
+	area = pcfg->area;
+	lsp_regenerate_schedule(area, area->is_type, 0);
+}
+
+/*
+ * XPath:
+ * /frr-isisd:isis/instance/segment-routing/prefix-sid-map/prefix-sid/sid-value-type
+ */
+int isis_instance_segment_routing_prefix_sid_map_prefix_sid_sid_value_type_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct sr_prefix_cfg *pcfg;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	pcfg = nb_running_get_entry(args->dnode, NULL, true);
+	pcfg->sid_type = yang_dnode_get_enum(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-isisd:isis/instance/segment-routing/prefix-sid-map/prefix-sid/sid-value
+ */
+int isis_instance_segment_routing_prefix_sid_map_prefix_sid_sid_value_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct sr_prefix_cfg *pcfg;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	pcfg = nb_running_get_entry(args->dnode, NULL, true);
+	pcfg->sid = yang_dnode_get_uint32(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-isisd:isis/instance/segment-routing/prefix-sid-map/prefix-sid/last-hop-behavior
+ */
+int isis_instance_segment_routing_prefix_sid_map_prefix_sid_last_hop_behavior_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct sr_prefix_cfg *pcfg;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	pcfg = nb_running_get_entry(args->dnode, NULL, true);
+	pcfg->last_hop_behavior = yang_dnode_get_enum(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/segment-routing/prefix-sid-map/prefix-sid/n-flag-clear
+ */
+int isis_instance_segment_routing_prefix_sid_map_prefix_sid_n_flag_clear_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct sr_prefix_cfg *pcfg;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	pcfg = nb_running_get_entry(args->dnode, NULL, true);
+	pcfg->n_flag_clear = yang_dnode_get_bool(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-isisd:isis/instance/segment-routing/algorithm-prefix-sids/algorithm-prefix-sid
+ */
+int isis_instance_segment_routing_algorithm_prefix_sid_create(
+	struct nb_cb_create_args *args)
+{
+	struct isis_area *area;
+	struct prefix prefix;
+	struct sr_prefix_cfg *pcfg;
+	uint32_t algorithm;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	yang_dnode_get_prefix(&prefix, args->dnode, "./prefix");
+	algorithm = yang_dnode_get_uint32(args->dnode, "./algo");
+
+	pcfg = isis_sr_cfg_prefix_add(area, &prefix, algorithm);
+	pcfg->algorithm = algorithm;
+	nb_running_set_entry(args->dnode, pcfg);
+
+	return NB_OK;
+}
+
+int isis_instance_segment_routing_algorithm_prefix_sid_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct sr_prefix_cfg *pcfg;
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	pcfg = nb_running_unset_entry(args->dnode);
+	area = pcfg->area;
+	isis_sr_cfg_prefix_del(pcfg);
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+int isis_instance_segment_routing_algorithm_prefix_sid_pre_validate(
+	struct nb_cb_pre_validate_args *args)
+{
+	const struct lyd_node *area_dnode;
+	struct isis_area *area;
+	struct prefix prefix;
+	uint32_t srgb_lbound;
+	uint32_t srgb_ubound;
+	uint32_t srgb_range;
+	uint32_t sid;
+	enum sr_sid_value_type sid_type;
+	struct isis_prefix_sid psid = {};
+
+	yang_dnode_get_prefix(&prefix, args->dnode, "./prefix");
+	srgb_lbound = yang_dnode_get_uint32(
+		args->dnode, "../../label-blocks/srgb/lower-bound");
+	srgb_ubound = yang_dnode_get_uint32(
+		args->dnode, "../../label-blocks/srgb/upper-bound");
+	sid = yang_dnode_get_uint32(args->dnode, "./sid-value");
+	sid_type = yang_dnode_get_enum(args->dnode, "./sid-value-type");
+
+	/* Check for invalid indexes/labels. */
+	srgb_range = srgb_ubound - srgb_lbound + 1;
+	psid.value = sid;
+	switch (sid_type) {
+	case SR_SID_VALUE_TYPE_INDEX:
+		if (sid >= srgb_range) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "SID index %u falls outside local SRGB range",
+				 sid);
+			return NB_ERR_VALIDATION;
+		}
+		break;
+	case SR_SID_VALUE_TYPE_ABSOLUTE:
+		if (!IS_MPLS_UNRESERVED_LABEL(sid)) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "Invalid absolute SID %u", sid);
+			return NB_ERR_VALIDATION;
+		}
+		SET_FLAG(psid.flags, ISIS_PREFIX_SID_VALUE);
+		SET_FLAG(psid.flags, ISIS_PREFIX_SID_LOCAL);
+		break;
+	}
+
+	/* Check for Prefix-SID collisions. */
+	area_dnode = yang_dnode_get_parent(args->dnode, "instance");
+	area = nb_running_get_entry(area_dnode, NULL, false);
+	if (!area)
+		return NB_OK;
+
+	for (int tree = SPFTREE_IPV4; tree < SPFTREE_COUNT; tree++) {
+		for (int level = ISIS_LEVEL1; level <= ISIS_LEVEL2; level++) {
+			struct isis_spftree *spftree;
+			struct isis_vertex *vertex_psid;
+
+			if (!(area->is_type & level))
+				continue;
+			spftree = area->spftree[tree][level - 1];
+			if (!spftree)
+				continue;
+
+			vertex_psid =
+				isis_spf_prefix_sid_lookup(spftree, &psid);
+			if (vertex_psid &&
+			    !prefix_same(&vertex_psid->N.ip.p.dest, &prefix)) {
+				snprintfrr(
+					args->errmsg, args->errmsg_len,
+					"Prefix-SID collision detected, SID %s %u is already in use by prefix %pFX (L%u)",
+					CHECK_FLAG(psid.flags,
+						   ISIS_PREFIX_SID_VALUE)
+						? "label"
+						: "index",
+					psid.value, &vertex_psid->N.ip.p.dest,
+					level);
+				return NB_ERR_VALIDATION;
+			}
+		}
+	}
+
+	return NB_OK;
+}
+
+void isis_instance_segment_routing_algorithm_prefix_sid_apply_finish(
+	struct nb_cb_apply_finish_args *args)
+{
+	struct sr_prefix_cfg *pcfg;
+	struct isis_area *area;
+
+	pcfg = nb_running_get_entry(args->dnode, NULL, true);
+	area = pcfg->area;
+	lsp_regenerate_schedule(area, area->is_type, 0);
+}
+
+/*
+ * XPath:
+ * /frr-isisd:isis/instance/segment-routing/algorithm-prefix-sids/algorithm-prefix-sid/sid-value-type
+ */
+int isis_instance_segment_routing_algorithm_prefix_sid_sid_value_type_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct sr_prefix_cfg *pcfg;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	pcfg = nb_running_get_entry(args->dnode, NULL, true);
+	pcfg->sid_type = yang_dnode_get_enum(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-isisd:isis/instance/segment-routing/algorithm-prefix-sids/algorithm-prefix-sid/sid-value
+ */
+int isis_instance_segment_routing_algorithm_prefix_sid_sid_value_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct sr_prefix_cfg *pcfg;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	pcfg = nb_running_get_entry(args->dnode, NULL, true);
+	pcfg->sid = yang_dnode_get_uint32(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-isisd:isis/instance/segment-routing/algorithm-prefix-sid-map/algorithm-prefix-sid/last-hop-behavior
+ */
+int isis_instance_segment_routing_algorithm_prefix_sid_last_hop_behavior_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct sr_prefix_cfg *pcfg;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	pcfg = nb_running_get_entry(args->dnode, NULL, true);
+	pcfg->last_hop_behavior = yang_dnode_get_enum(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-isisd:isis/instance/segment-routing/algorithm-prefix-sids/algorithm-prefix-sid/n-flag-clear
+ */
+int isis_instance_segment_routing_algorithm_prefix_sid_n_flag_clear_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct sr_prefix_cfg *pcfg;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	pcfg = nb_running_get_entry(args->dnode, NULL, true);
+	pcfg->n_flag_clear = yang_dnode_get_bool(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/flex-algos/flex-algo
+ */
+int isis_instance_flex_algo_create(struct nb_cb_create_args *args)
+{
+	struct isis_area *area;
+	struct flex_algo *fa;
+	bool advertise;
+	uint32_t algorithm;
+	uint32_t priority = FLEX_ALGO_PRIO_DEFAULT;
+	struct isis_flex_algo_alloc_arg arg;
+
+	algorithm = yang_dnode_get_uint32(args->dnode, "./flex-algo");
+	advertise = yang_dnode_exists(args->dnode, "./advertise-definition");
+
+	switch (args->event) {
+	case NB_EV_APPLY:
+		area = nb_running_get_entry(args->dnode, NULL, true);
+		arg.algorithm = algorithm;
+		arg.area = area;
+		fa = flex_algo_alloc(area->flex_algos, algorithm, &arg);
+		fa->priority = priority;
+		fa->advertise_definition = advertise;
+		if (area->admin_group_send_zero) {
+			admin_group_allow_explicit_zero(
+				&fa->admin_group_exclude_any);
+			admin_group_allow_explicit_zero(
+				&fa->admin_group_include_any);
+			admin_group_allow_explicit_zero(
+				&fa->admin_group_include_all);
+		}
+		lsp_regenerate_schedule(area, area->is_type, 0);
+		break;
+	case NB_EV_VALIDATE:
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	}
+
+	return NB_OK;
+}
+
+int isis_instance_flex_algo_destroy(struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+	uint32_t algorithm;
+
+	algorithm = yang_dnode_get_uint32(args->dnode, "./flex-algo");
+	area = nb_running_get_entry(args->dnode, NULL, true);
+
+	switch (args->event) {
+	case NB_EV_APPLY:
+		flex_algo_delete(area->flex_algos, algorithm);
+		lsp_regenerate_schedule(area, area->is_type, 0);
+		break;
+	case NB_EV_VALIDATE:
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/flex-algos/flex-algo/advertise-definition
+ */
+int isis_instance_flex_algo_advertise_definition_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	struct flex_algo *fa;
+	bool advertise;
+	uint32_t algorithm;
+
+
+	algorithm = yang_dnode_get_uint32(args->dnode, "./../flex-algo");
+	advertise = yang_dnode_exists(args->dnode, "./../advertise-definition");
+
+	switch (args->event) {
+	case NB_EV_APPLY:
+		area = nb_running_get_entry(args->dnode, NULL, true);
+		fa = flex_algo_lookup(area->flex_algos, algorithm);
+		if (!fa) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "flex-algo object not found");
+			return NB_ERR_RESOURCE;
+		}
+		fa->advertise_definition = advertise;
+		lsp_regenerate_schedule(area, area->is_type, 0);
+		break;
+	case NB_EV_VALIDATE:
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	}
+
+	return NB_OK;
+}
+
+int isis_instance_flex_algo_advertise_definition_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+	struct flex_algo *fa;
+	uint32_t algorithm;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+
+	algorithm = yang_dnode_get_uint32(args->dnode, "./../flex-algo");
+
+	switch (args->event) {
+	case NB_EV_APPLY:
+		fa = flex_algo_lookup(area->flex_algos, algorithm);
+		if (!fa) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "flex-algo object not found");
+			return NB_ERR_RESOURCE;
+		}
+		fa->advertise_definition = false;
+		lsp_regenerate_schedule(area, area->is_type, 0);
+		break;
+	case NB_EV_VALIDATE:
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	}
+
+	return NB_OK;
+}
+
+static int isis_instance_flex_algo_affinity_set(struct nb_cb_create_args *args,
+						int type)
+{
+	struct affinity_map *map;
+	struct isis_area *area;
+	struct admin_group *ag;
+	struct flex_algo *fa;
+	uint32_t algorithm;
+	const char *val;
+
+	algorithm = yang_dnode_get_uint32(args->dnode, "../../flex-algo");
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	val = yang_dnode_get_string(args->dnode, ".");
+
+	switch (args->event) {
+	case NB_EV_VALIDATE:
+		fa = flex_algo_lookup(area->flex_algos, algorithm);
+		if (!fa) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "flex-algo object not found");
+			return NB_ERR_RESOURCE;
+		}
+		map = affinity_map_get(val);
+		if (!map) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "affinity map %s isn't found", val);
+			return NB_ERR_VALIDATION;
+		}
+		break;
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	case NB_EV_APPLY:
+		fa = flex_algo_lookup(area->flex_algos, algorithm);
+		if (!fa) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "flex-algo object not found");
+			return NB_ERR_RESOURCE;
+		}
+		map = affinity_map_get(val);
+		if (!map) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "affinity map %s isn't found", val);
+			return NB_ERR_RESOURCE;
+		}
+		if (type == AFFINITY_INCLUDE_ANY)
+			ag = &fa->admin_group_include_any;
+		else if (type == AFFINITY_INCLUDE_ALL)
+			ag = &fa->admin_group_include_all;
+		else if (type == AFFINITY_EXCLUDE_ANY)
+			ag = &fa->admin_group_exclude_any;
+		else
+			break;
+
+		admin_group_set(ag, map->bit_position);
+		lsp_regenerate_schedule(area, area->is_type, 0);
+		break;
+	}
+
+	return NB_OK;
+}
+
+static int
+isis_instance_flex_algo_affinity_unset(struct nb_cb_destroy_args *args,
+				       int type)
+{
+	struct affinity_map *map;
+	struct isis_area *area;
+	struct admin_group *ag;
+	struct flex_algo *fa;
+	uint32_t algorithm;
+	const char *val;
+
+	algorithm = yang_dnode_get_uint32(args->dnode, "../../flex-algo");
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	val = yang_dnode_get_string(args->dnode, ".");
+
+	switch (args->event) {
+	case NB_EV_VALIDATE:
+		fa = flex_algo_lookup(area->flex_algos, algorithm);
+		if (!fa) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "flex-algo object not found");
+			return NB_ERR_RESOURCE;
+		}
+		map = affinity_map_get(val);
+		if (!map) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "affinity map %s isn't found", val);
+			return NB_ERR_VALIDATION;
+		}
+		break;
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	case NB_EV_APPLY:
+		fa = flex_algo_lookup(area->flex_algos, algorithm);
+		if (!fa) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "flex-algo object not found");
+			return NB_ERR_RESOURCE;
+		}
+		map = affinity_map_get(val);
+		if (!map) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "affinity map %s isn't found", val);
+			return NB_ERR_RESOURCE;
+		}
+		if (type == AFFINITY_INCLUDE_ANY)
+			ag = &fa->admin_group_include_any;
+		else if (type == AFFINITY_INCLUDE_ALL)
+			ag = &fa->admin_group_include_all;
+		else if (type == AFFINITY_EXCLUDE_ANY)
+			ag = &fa->admin_group_exclude_any;
+		else
+			break;
+
+		admin_group_unset(ag, map->bit_position);
+		if (area->admin_group_send_zero)
+			admin_group_allow_explicit_zero(ag);
+		lsp_regenerate_schedule(area, area->is_type, 0);
+		break;
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-isisd:isis/instance/flex-algos/flex-algo/affinity-include-anies/affinity-include-any
+ */
+int isis_instance_flex_algo_affinity_include_any_create(
+	struct nb_cb_create_args *args)
+{
+	return isis_instance_flex_algo_affinity_set(args, AFFINITY_INCLUDE_ANY);
+}
+
+int isis_instance_flex_algo_affinity_include_any_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	return isis_instance_flex_algo_affinity_unset(args,
+						      AFFINITY_INCLUDE_ANY);
+}
+
+/*
+ * XPath:
+ * /frr-isisd:isis/instance/flex-algos/flex-algo/affinity-include-alls/affinity-include-all
+ */
+int isis_instance_flex_algo_affinity_include_all_create(
+	struct nb_cb_create_args *args)
+{
+	return isis_instance_flex_algo_affinity_set(args, AFFINITY_INCLUDE_ALL);
+}
+
+int isis_instance_flex_algo_affinity_include_all_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	return isis_instance_flex_algo_affinity_unset(args,
+						      AFFINITY_INCLUDE_ALL);
+}
+
+/*
+ * XPath:
+ * /frr-isisd:isis/instance/flex-algos/flex-algo/affinity-exclude-anies/affinity-exclude-any
+ */
+int isis_instance_flex_algo_affinity_exclude_any_create(
+	struct nb_cb_create_args *args)
+{
+	return isis_instance_flex_algo_affinity_set(args, AFFINITY_EXCLUDE_ANY);
+}
+
+int isis_instance_flex_algo_affinity_exclude_any_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	return isis_instance_flex_algo_affinity_unset(args,
+						      AFFINITY_EXCLUDE_ANY);
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/flex-algos/flex-algo/prefix-metric
+ */
+
+int isis_instance_flex_algo_prefix_metric_create(struct nb_cb_create_args *args)
+{
+	struct isis_area *area;
+	const char *area_tag;
+	struct flex_algo *fa;
+	uint32_t algorithm;
+
+	area_tag = yang_dnode_get_string(args->dnode, "../../../area-tag");
+	area = isis_area_lookup(area_tag, VRF_DEFAULT);
+	if (!area)
+		return NB_ERR_RESOURCE;
+
+	algorithm = yang_dnode_get_uint32(args->dnode, "./../flex-algo");
+
+	switch (args->event) {
+	case NB_EV_APPLY:
+		fa = flex_algo_lookup(area->flex_algos, algorithm);
+		if (!fa) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "flex-algo object not found");
+			return NB_ERR_RESOURCE;
+		}
+		SET_FLAG(fa->flags, FAD_FLAG_M);
+		lsp_regenerate_schedule(area, area->is_type, 0);
+		break;
+	case NB_EV_VALIDATE:
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	}
+
+	return NB_OK;
+}
+
+int isis_instance_flex_algo_prefix_metric_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+	const char *area_tag;
+	struct flex_algo *fa;
+	uint32_t algorithm;
+
+	area_tag = yang_dnode_get_string(args->dnode, "../../../area-tag");
+	area = isis_area_lookup(area_tag, VRF_DEFAULT);
+	if (!area)
+		return NB_ERR_RESOURCE;
+
+	algorithm = yang_dnode_get_uint32(args->dnode, "./../flex-algo");
+
+	switch (args->event) {
+	case NB_EV_APPLY:
+		fa = flex_algo_lookup(area->flex_algos, algorithm);
+		if (!fa) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "flex-algo object not found");
+			return NB_ERR_RESOURCE;
+		}
+		UNSET_FLAG(fa->flags, FAD_FLAG_M);
+		lsp_regenerate_schedule(area, area->is_type, 0);
+		break;
+	case NB_EV_VALIDATE:
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	}
+
+	return NB_OK;
+}
+
+static int isis_instance_flex_algo_dplane_set(struct nb_cb_create_args *args,
+					      int type)
+{
+	struct isis_area *area;
+	const char *area_tag;
+	struct flex_algo *fa;
+	uint32_t algorithm;
+
+	area_tag = yang_dnode_get_string(args->dnode, "../../../area-tag");
+	area = isis_area_lookup(area_tag, VRF_DEFAULT);
+	if (!area)
+		return NB_ERR_RESOURCE;
+
+	algorithm = yang_dnode_get_uint32(args->dnode, "./../flex-algo");
+
+	switch (args->event) {
+	case NB_EV_APPLY:
+		fa = flex_algo_lookup(area->flex_algos, algorithm);
+		if (!fa) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "flex-algo object not found");
+			return NB_ERR_RESOURCE;
+		}
+		SET_FLAG(fa->dataplanes, type);
+		lsp_regenerate_schedule(area, area->is_type, 0);
+		break;
+	case NB_EV_VALIDATE:
+		if (type == FLEX_ALGO_SRV6 || type == FLEX_ALGO_IP) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "%s Flex-algo dataplane is not yet supported.",
+				 type == FLEX_ALGO_SRV6 ? "SRv6" : "IP");
+			return NB_ERR_VALIDATION;
+		}
+		break;
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	}
+
+	return NB_OK;
+}
+
+static int isis_instance_flex_algo_dplane_unset(struct nb_cb_destroy_args *args,
+						int type)
+{
+	struct isis_area *area;
+	const char *area_tag;
+	struct flex_algo *fa;
+	uint32_t algorithm;
+
+	area_tag = yang_dnode_get_string(args->dnode, "../../../area-tag");
+	area = isis_area_lookup(area_tag, VRF_DEFAULT);
+	if (!area)
+		return NB_ERR_RESOURCE;
+
+	algorithm = yang_dnode_get_uint32(args->dnode, "./../flex-algo");
+
+	switch (args->event) {
+	case NB_EV_APPLY:
+		fa = flex_algo_lookup(area->flex_algos, algorithm);
+		if (!fa) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "flex-algo object not found");
+			return NB_ERR_RESOURCE;
+		}
+		UNSET_FLAG(fa->dataplanes, type);
+		lsp_regenerate_schedule(area, area->is_type, 0);
+		break;
+	case NB_EV_VALIDATE:
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/flex-algos/flex-algo/dplane-sr-mpls
+ */
+
+int isis_instance_flex_algo_dplane_sr_mpls_create(
+	struct nb_cb_create_args *args)
+{
+	return isis_instance_flex_algo_dplane_set(args, FLEX_ALGO_SR_MPLS);
+}
+
+int isis_instance_flex_algo_dplane_sr_mpls_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	return isis_instance_flex_algo_dplane_unset(args, FLEX_ALGO_SR_MPLS);
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/flex-algos/flex-algo/dplane-srv6
+ */
+
+int isis_instance_flex_algo_dplane_srv6_create(struct nb_cb_create_args *args)
+{
+	return isis_instance_flex_algo_dplane_set(args, FLEX_ALGO_SRV6);
+}
+
+int isis_instance_flex_algo_dplane_srv6_destroy(struct nb_cb_destroy_args *args)
+{
+	return isis_instance_flex_algo_dplane_unset(args, FLEX_ALGO_SRV6);
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/flex-algos/flex-algo/dplane-ip
+ */
+
+int isis_instance_flex_algo_dplane_ip_create(struct nb_cb_create_args *args)
+{
+	return isis_instance_flex_algo_dplane_set(args, FLEX_ALGO_IP);
+}
+
+int isis_instance_flex_algo_dplane_ip_destroy(struct nb_cb_destroy_args *args)
+{
+	return isis_instance_flex_algo_dplane_unset(args, FLEX_ALGO_IP);
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/flex-algos/flex-algo/metric-type
+ */
+
+int isis_instance_flex_algo_metric_type_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	const char *area_tag;
+	struct flex_algo *fa;
+	uint32_t algorithm;
+	enum flex_algo_metric_type metric_type;
+
+	area_tag = yang_dnode_get_string(args->dnode, "../../../area-tag");
+	area = isis_area_lookup(area_tag, VRF_DEFAULT);
+	if (!area)
+		return NB_ERR_RESOURCE;
+
+	algorithm = yang_dnode_get_uint32(args->dnode, "./../flex-algo");
+	metric_type = yang_dnode_get_enum(args->dnode, NULL);
+
+	switch (args->event) {
+	case NB_EV_APPLY:
+		fa = flex_algo_lookup(area->flex_algos, algorithm);
+		if (!fa) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "flex-algo object not found");
+			return NB_ERR_RESOURCE;
+		}
+		fa->metric_type = metric_type;
+		lsp_regenerate_schedule(area, area->is_type, 0);
+		break;
+	case NB_EV_VALIDATE:
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/flex-algos/flex-algo/priority
+ */
+
+int isis_instance_flex_algo_priority_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	const char *area_tag;
+	struct flex_algo *fa;
+	uint32_t algorithm;
+	uint32_t priority;
+
+	area_tag = yang_dnode_get_string(args->dnode, "../../../area-tag");
+	area = isis_area_lookup(area_tag, VRF_DEFAULT);
+	if (!area)
+		return NB_ERR_RESOURCE;
+
+	algorithm = yang_dnode_get_uint32(args->dnode, "./../flex-algo");
+	priority = yang_dnode_get_uint32(args->dnode, NULL);
+
+	switch (args->event) {
+	case NB_EV_APPLY:
+		fa = flex_algo_lookup(area->flex_algos, algorithm);
+		if (!fa) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "flex-algo object not found");
+			return NB_ERR_RESOURCE;
+		}
+		fa->priority = priority;
+		lsp_regenerate_schedule(area, area->is_type, 0);
+		break;
+	case NB_EV_VALIDATE:
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	}
+
+	return NB_OK;
+}
+
+int isis_instance_flex_algo_priority_destroy(struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+	const char *area_tag;
+	struct flex_algo *fa;
+	uint32_t algorithm;
+	uint32_t priority = FLEX_ALGO_PRIO_DEFAULT;
+
+	area_tag = yang_dnode_get_string(args->dnode, "../../../area-tag");
+	area = isis_area_lookup(area_tag, VRF_DEFAULT);
+	if (!area)
+		return NB_ERR_RESOURCE;
+
+	algorithm = yang_dnode_get_uint32(args->dnode, "./../flex-algo");
+	priority = yang_dnode_get_uint32(args->dnode, NULL);
+
+	switch (args->event) {
+	case NB_EV_APPLY:
+		fa = flex_algo_lookup(area->flex_algos, algorithm);
+		if (!fa) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "flex-algo object not found");
+			return NB_ERR_RESOURCE;
+		}
+		fa->priority = priority;
+		lsp_regenerate_schedule(area, area->is_type, 0);
+		break;
+	case NB_EV_VALIDATE:
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/segment-routing-srv6/enabled
+ */
+int isis_instance_segment_routing_srv6_enabled_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->srv6db.config.enabled = yang_dnode_get_bool(args->dnode, NULL);
+
+	if (area->srv6db.config.enabled) {
+		if (IS_DEBUG_EVENTS)
+			zlog_debug(
+				"Segment Routing over IPv6 (SRv6): OFF -> ON");
+	} else {
+		if (IS_DEBUG_EVENTS)
+			zlog_debug(
+				"Segment Routing over IPv6 (SRv6): ON -> OFF");
+	}
+
+	/* Regenerate LSPs to advertise SRv6 capabilities or signal that the
+	 * node is no longer SRv6-capable. */
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/segment-routing-srv6/locator
+ */
+int isis_instance_segment_routing_srv6_locator_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	const char *loc_name;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(lyd_parent(lyd_parent(args->dnode)), NULL,
+				    true);
+
+	loc_name = yang_dnode_get_string(args->dnode, NULL);
+
+	if (strncmp(loc_name, area->srv6db.config.srv6_locator_name,
+		    sizeof(area->srv6db.config.srv6_locator_name)) == 0) {
+		snprintf(args->errmsg, args->errmsg_len,
+			 "SRv6 locator %s is already configured", loc_name);
+		return NB_ERR_NO_CHANGES;
+	}
+
+	/* Remove previously configured locator */
+	if (strncmp(area->srv6db.config.srv6_locator_name, "",
+		    sizeof(area->srv6db.config.srv6_locator_name)) != 0) {
+		sr_debug("Unsetting previously configured SRv6 locator");
+		if (!isis_srv6_locator_unset(area)) {
+			zlog_warn("Failed to unset SRv6 locator");
+			return NB_ERR;
+		}
+	}
+
+	strlcpy(area->srv6db.config.srv6_locator_name, loc_name,
+		sizeof(area->srv6db.config.srv6_locator_name));
+
+	sr_debug("Configured SRv6 locator %s for IS-IS area %s", loc_name,
+		 area->area_tag);
+
+	sr_debug("Trying to get a chunk from locator %s for IS-IS area %s",
+		 loc_name, area->area_tag);
+
+	if (isis_zebra_srv6_manager_get_locator_chunk(loc_name) < 0)
+		return NB_ERR;
+
+	return NB_OK;
+}
+
+int isis_instance_segment_routing_srv6_locator_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+	const char *loc_name;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(lyd_parent(lyd_parent(args->dnode)), NULL,
+				    true);
+
+	loc_name = yang_dnode_get_string(args->dnode, NULL);
+
+	sr_debug("Trying to unset SRv6 locator %s", loc_name);
+
+	if (strncmp(loc_name, area->srv6db.config.srv6_locator_name,
+		    sizeof(area->srv6db.config.srv6_locator_name)) != 0) {
+		sr_debug("SRv6 locator %s is not configured", loc_name);
+		snprintf(args->errmsg, args->errmsg_len,
+			 "SRv6 locator %s is not configured", loc_name);
+		return NB_ERR_NO_CHANGES;
+	}
+
+	if (!isis_srv6_locator_unset(area)) {
+		zlog_warn("Failed to unset SRv6 locator");
+		return NB_ERR;
+	}
+
+	sr_debug("Deleted SRv6 locator %s for IS-IS area %s", loc_name,
+		 area->area_tag);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/segment-routing-srv6/msd/node-msd/max-segs-left
+ */
+int isis_instance_segment_routing_srv6_msd_node_msd_max_segs_left_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->srv6db.config.max_seg_left_msd = yang_dnode_get_uint8(args->dnode,
+								    NULL);
+
+	/* Update and regenerate LSP */
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/segment-routing-srv6/msd/node-msd/max-end-pop
+ */
+int isis_instance_segment_routing_srv6_msd_node_msd_max_end_pop_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->srv6db.config.max_end_pop_msd = yang_dnode_get_uint8(args->dnode,
+								   NULL);
+
+	/* Update and regenerate LSP */
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/segment-routing-srv6/msd/node-msd/max-h-encaps
+ */
+int isis_instance_segment_routing_srv6_msd_node_msd_max_h_encaps_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->srv6db.config.max_h_encaps_msd = yang_dnode_get_uint8(args->dnode,
+								    NULL);
+
+	/* Update and regenerate LSP */
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/segment-routing-srv6/msd/node-msd/max-end-d
+ */
+int isis_instance_segment_routing_srv6_msd_node_msd_max_end_d_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	area->srv6db.config.max_end_d_msd = yang_dnode_get_uint8(args->dnode,
+								 NULL);
+
+	/* Update and regenerate LSP */
+	lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/segment-routing-srv6/interface
+ */
+int isis_instance_segment_routing_srv6_interface_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	const char *ifname;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(lyd_parent(lyd_parent(args->dnode)), NULL,
+				    true);
+
+	ifname = yang_dnode_get_string(args->dnode, NULL);
+
+	sr_debug("Changing SRv6 interface for IS-IS area %s to %s",
+		 area->area_tag, ifname);
+
+	isis_srv6_interface_set(area, ifname);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/mpls/ldp-sync
+ */
+int isis_instance_mpls_ldp_sync_create(struct nb_cb_create_args *args)
+{
+	struct isis_area *area;
+	const char *vrfname;
+
+	switch (args->event) {
+	case NB_EV_VALIDATE:
+		vrfname = yang_dnode_get_string(
+			lyd_parent(lyd_parent(args->dnode)), "./vrf");
+
+		if (strcmp(vrfname, VRF_DEFAULT_NAME)) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "LDP-Sync only runs on Default VRF");
+			return NB_ERR_VALIDATION;
+		}
+		break;
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	case NB_EV_APPLY:
+		area = nb_running_get_entry(args->dnode, NULL, true);
+		isis_area_ldp_sync_enable(area);
+		break;
+	}
+	return NB_OK;
+}
+
+int isis_instance_mpls_ldp_sync_destroy(struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	area = nb_running_get_entry(args->dnode, NULL, true);
+	isis_area_ldp_sync_disable(area);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-isisd:isis/instance/mpls/ldp-sync/holddown
+ */
+int isis_instance_mpls_ldp_sync_holddown_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	uint16_t holddown;
+	const char *vrfname;
+
+	switch (args->event) {
+	case NB_EV_VALIDATE:
+		vrfname = yang_dnode_get_string(
+			lyd_parent(lyd_parent(lyd_parent(args->dnode))),
+			"./vrf");
+
+		if (strcmp(vrfname, VRF_DEFAULT_NAME)) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "LDP-Sync only runs on Default VRF");
+			return NB_ERR_VALIDATION;
+		}
+		break;
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	case NB_EV_APPLY:
+		area = nb_running_get_entry(args->dnode, NULL, true);
+		holddown = yang_dnode_get_uint16(args->dnode, NULL);
+		isis_area_ldp_sync_set_holddown(area, holddown);
+		break;
+	}
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis
+ */
+int lib_interface_isis_create(struct nb_cb_create_args *args)
+{
+	struct interface *ifp;
+	struct isis_circuit *circuit = NULL;
+	const char *area_tag = yang_dnode_get_string(args->dnode, "./area-tag");
+
+	switch (args->event) {
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+	case NB_EV_VALIDATE:
+		break;
+	case NB_EV_APPLY:
+		ifp = nb_running_get_entry(args->dnode, NULL, true);
+		circuit = isis_circuit_new(ifp, area_tag);
+		nb_running_set_entry(args->dnode, circuit);
+		break;
+	}
+
+	return NB_OK;
+}
+
+int lib_interface_isis_destroy(struct nb_cb_destroy_args *args)
+{
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_unset_entry(args->dnode);
+
+	isis_circuit_del(circuit);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/area-tag
+ */
+int lib_interface_isis_area_tag_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+
+	if (args->event == NB_EV_VALIDATE) {
+		circuit = nb_running_get_entry_non_rec(lyd_parent(args->dnode),
+						       NULL, false);
+		if (circuit) {
+			snprintf(args->errmsg, args->errmsg_len,
+				 "Changing area tag is not allowed");
+			return NB_ERR_VALIDATION;
+		}
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/circuit-type
+ */
+int lib_interface_isis_circuit_type_modify(struct nb_cb_modify_args *args)
+{
+	int circ_type = yang_dnode_get_enum(args->dnode, NULL);
+	struct isis_circuit *circuit;
+
+	switch (args->event) {
+	case NB_EV_VALIDATE:
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	case NB_EV_APPLY:
+		circuit = nb_running_get_entry(args->dnode, NULL, true);
+		circuit->is_type_config = circ_type;
+		isis_circuit_is_type_set(circuit, circ_type);
+		break;
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/ipv4-routing
+ */
+int lib_interface_isis_ipv4_routing_modify(struct nb_cb_modify_args *args)
+{
+	bool ipv4, ipv6;
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	ipv4 = yang_dnode_get_bool(args->dnode, NULL);
+	ipv6 = yang_dnode_get_bool(args->dnode, "../ipv6-routing");
+	isis_circuit_af_set(circuit, ipv4, ipv6);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/ipv6-routing
+ */
+int lib_interface_isis_ipv6_routing_modify(struct nb_cb_modify_args *args)
+{
+	bool ipv4, ipv6;
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	ipv4 = yang_dnode_get_bool(args->dnode, "../ipv4-routing");
+	ipv6 = yang_dnode_get_bool(args->dnode, NULL);
+	isis_circuit_af_set(circuit, ipv4, ipv6);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/bfd-monitoring
+ */
+void lib_interface_isis_bfd_monitoring_apply_finish(
+	struct nb_cb_apply_finish_args *args)
+{
+	struct isis_circuit *circuit;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	isis_bfd_circuit_cmd(circuit);
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/bfd-monitoring/enabled
+ */
+int lib_interface_isis_bfd_monitoring_enabled_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->bfd_config.enabled = yang_dnode_get_bool(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/bfd-monitoring/profile
+ */
+int lib_interface_isis_bfd_monitoring_profile_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	XFREE(MTYPE_TMP, circuit->bfd_config.profile);
+	circuit->bfd_config.profile =
+		XSTRDUP(MTYPE_TMP, yang_dnode_get_string(args->dnode, NULL));
+
+	return NB_OK;
+}
+
+int lib_interface_isis_bfd_monitoring_profile_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	XFREE(MTYPE_TMP, circuit->bfd_config.profile);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/csnp-interval/level-1
+ */
+int lib_interface_isis_csnp_interval_level_1_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->csnp_interval[0] = yang_dnode_get_uint16(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/csnp-interval/level-2
+ */
+int lib_interface_isis_csnp_interval_level_2_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->csnp_interval[1] = yang_dnode_get_uint16(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/psnp-interval/level-1
+ */
+int lib_interface_isis_psnp_interval_level_1_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->psnp_interval[0] = yang_dnode_get_uint16(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/psnp-interval/level-2
+ */
+int lib_interface_isis_psnp_interval_level_2_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->psnp_interval[1] = yang_dnode_get_uint16(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/hello/padding
+ */
+int lib_interface_isis_hello_padding_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->pad_hellos = yang_dnode_get_enum(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/hello/interval/level-1
+ */
+int lib_interface_isis_hello_interval_level_1_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+	uint32_t interval;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	interval = yang_dnode_get_uint32(args->dnode, NULL);
+	circuit->hello_interval[0] = interval;
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/hello/interval/level-2
+ */
+int lib_interface_isis_hello_interval_level_2_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+	uint32_t interval;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	interval = yang_dnode_get_uint32(args->dnode, NULL);
+	circuit->hello_interval[1] = interval;
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/hello/multiplier/level-1
+ */
+int lib_interface_isis_hello_multiplier_level_1_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+	uint16_t multi;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	multi = yang_dnode_get_uint16(args->dnode, NULL);
+	circuit->hello_multiplier[0] = multi;
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/hello/multiplier/level-2
+ */
+int lib_interface_isis_hello_multiplier_level_2_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+	uint16_t multi;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	multi = yang_dnode_get_uint16(args->dnode, NULL);
+	circuit->hello_multiplier[1] = multi;
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/metric/level-1
+ */
+int lib_interface_isis_metric_level_1_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+	unsigned int met;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	met = yang_dnode_get_uint32(args->dnode, NULL);
+	isis_circuit_metric_set(circuit, IS_LEVEL_1, met);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/metric/level-2
+ */
+int lib_interface_isis_metric_level_2_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+	unsigned int met;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	met = yang_dnode_get_uint32(args->dnode, NULL);
+	isis_circuit_metric_set(circuit, IS_LEVEL_2, met);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/priority/level-1
+ */
+int lib_interface_isis_priority_level_1_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->priority[0] = yang_dnode_get_uint8(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/priority/level-2
+ */
+int lib_interface_isis_priority_level_2_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->priority[1] = yang_dnode_get_uint8(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/network-type
+ */
+int lib_interface_isis_network_type_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+	int net_type = yang_dnode_get_enum(args->dnode, NULL);
+
+	switch (args->event) {
+	case NB_EV_VALIDATE:
+		circuit = nb_running_get_entry(args->dnode, NULL, false);
+		if (!circuit)
+			break;
+		if (circuit->circ_type == CIRCUIT_T_LOOPBACK) {
+			snprintf(
+				args->errmsg, args->errmsg_len,
+				"Cannot change network type on loopback interface");
+			return NB_ERR_VALIDATION;
+		}
+		if (net_type == CIRCUIT_T_BROADCAST
+		    && circuit->state == C_STATE_UP
+		    && !if_is_broadcast(circuit->interface)) {
+			snprintf(
+				args->errmsg, args->errmsg_len,
+				"Cannot configure non-broadcast interface for broadcast operation");
+			return NB_ERR_VALIDATION;
+		}
+		break;
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	case NB_EV_APPLY:
+		circuit = nb_running_get_entry(args->dnode, NULL, true);
+		isis_circuit_circ_type_set(circuit, net_type);
+		break;
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/passive
+ */
+int lib_interface_isis_passive_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+	bool passive = yang_dnode_get_bool(args->dnode, NULL);
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	isis_circuit_passive_set(circuit, passive);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/password
+ */
+int lib_interface_isis_password_create(struct nb_cb_create_args *args)
+{
+	return NB_OK;
+}
+
+int lib_interface_isis_password_destroy(struct nb_cb_destroy_args *args)
+{
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	isis_circuit_passwd_unset(circuit);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/password/password
+ */
+int lib_interface_isis_password_password_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+	const char *password;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	password = yang_dnode_get_string(args->dnode, NULL);
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+
+	isis_circuit_passwd_set(circuit, circuit->passwd.type, password);
+
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/password/password-type
+ */
+int lib_interface_isis_password_password_type_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+	uint8_t pass_type;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	pass_type = yang_dnode_get_enum(args->dnode, NULL);
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->passwd.type = pass_type;
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/disable-three-way-handshake
+ */
+int lib_interface_isis_disable_three_way_handshake_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->disable_threeway_adj = yang_dnode_get_bool(args->dnode, NULL);
+
+	return NB_OK;
+}
+
+static int lib_interface_isis_multi_topology_common(
+	enum nb_event event, const struct lyd_node *dnode, char *errmsg,
+	size_t errmsg_len, uint16_t mtid)
+{
+	struct isis_circuit *circuit;
+	bool value;
+
+	switch (event) {
+	case NB_EV_VALIDATE:
+		circuit = nb_running_get_entry(dnode, NULL, false);
+		if (circuit && circuit->area && circuit->area->oldmetric) {
+			snprintf(
+				errmsg, errmsg_len,
+				"Multi topology IS-IS can only be used with wide metrics");
+			return NB_ERR_VALIDATION;
+		}
+		break;
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	case NB_EV_APPLY:
+		circuit = nb_running_get_entry(dnode, NULL, true);
+		value = yang_dnode_get_bool(dnode, NULL);
+		isis_circuit_mt_enabled_set(circuit, mtid, value);
+		break;
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/multi-topology/standard
+ */
+int lib_interface_isis_multi_topology_standard_modify(
+	struct nb_cb_modify_args *args)
+{
+	return lib_interface_isis_multi_topology_common(
+		args->event, args->dnode, args->errmsg, args->errmsg_len,
+		ISIS_MT_STANDARD);
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/multi-topology/ipv4-multicast
+ */
+int lib_interface_isis_multi_topology_ipv4_multicast_modify(
+	struct nb_cb_modify_args *args)
+{
+	return lib_interface_isis_multi_topology_common(
+		args->event, args->dnode, args->errmsg, args->errmsg_len,
+		ISIS_MT_IPV4_MULTICAST);
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/multi-topology/ipv4-management
+ */
+int lib_interface_isis_multi_topology_ipv4_management_modify(
+	struct nb_cb_modify_args *args)
+{
+	return lib_interface_isis_multi_topology_common(
+		args->event, args->dnode, args->errmsg, args->errmsg_len,
+		ISIS_MT_IPV4_MGMT);
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/multi-topology/ipv6-unicast
+ */
+int lib_interface_isis_multi_topology_ipv6_unicast_modify(
+	struct nb_cb_modify_args *args)
+{
+	return lib_interface_isis_multi_topology_common(
+		args->event, args->dnode, args->errmsg, args->errmsg_len,
+		ISIS_MT_IPV6_UNICAST);
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/multi-topology/ipv6-multicast
+ */
+int lib_interface_isis_multi_topology_ipv6_multicast_modify(
+	struct nb_cb_modify_args *args)
+{
+	return lib_interface_isis_multi_topology_common(
+		args->event, args->dnode, args->errmsg, args->errmsg_len,
+		ISIS_MT_IPV6_MULTICAST);
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/multi-topology/ipv6-management
+ */
+int lib_interface_isis_multi_topology_ipv6_management_modify(
+	struct nb_cb_modify_args *args)
+{
+	return lib_interface_isis_multi_topology_common(
+		args->event, args->dnode, args->errmsg, args->errmsg_len,
+		ISIS_MT_IPV6_MGMT);
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/multi-topology/ipv6-dstsrc
+ */
+int lib_interface_isis_multi_topology_ipv6_dstsrc_modify(
+	struct nb_cb_modify_args *args)
+{
+	return lib_interface_isis_multi_topology_common(
+		args->event, args->dnode, args->errmsg, args->errmsg_len,
+		ISIS_MT_IPV6_DSTSRC);
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/mpls/ldp-sync
+ */
+int lib_interface_isis_mpls_ldp_sync_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+	struct ldp_sync_info *ldp_sync_info;
+	bool ldp_sync_enable;
+
+	switch (args->event) {
+	case NB_EV_VALIDATE:
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	case NB_EV_APPLY:
+		circuit = nb_running_get_entry(args->dnode, NULL, true);
+		ldp_sync_enable = yang_dnode_get_bool(args->dnode, NULL);
+
+		ldp_sync_info = circuit->ldp_sync_info;
+
+		SET_FLAG(ldp_sync_info->flags, LDP_SYNC_FLAG_IF_CONFIG);
+		ldp_sync_info->enabled = ldp_sync_enable;
+
+		if (circuit->area) {
+			if (ldp_sync_enable)
+				isis_if_ldp_sync_enable(circuit);
+			else
+				isis_if_ldp_sync_disable(circuit);
+		}
+		break;
+	}
+	return NB_OK;
+}
+
+/*
+ * XPath: /frr-interface:lib/interface/frr-isisd:isis/mpls/holddown
+ */
+int lib_interface_isis_mpls_holddown_modify(struct nb_cb_modify_args *args)
+{
+	struct isis_circuit *circuit;
+	struct ldp_sync_info *ldp_sync_info;
+	uint16_t holddown;
+
+	switch (args->event) {
+	case NB_EV_VALIDATE:
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	case NB_EV_APPLY:
+		circuit = nb_running_get_entry(args->dnode, NULL, true);
+		holddown = yang_dnode_get_uint16(args->dnode, NULL);
+
+		ldp_sync_info = circuit->ldp_sync_info;
+
+		SET_FLAG(ldp_sync_info->flags, LDP_SYNC_FLAG_HOLDDOWN);
+		ldp_sync_info->holddown = holddown;
+		break;
+	}
+	return NB_OK;
+}
+
+int lib_interface_isis_mpls_holddown_destroy(struct nb_cb_destroy_args *args)
+{
+	struct isis_circuit *circuit;
+	struct ldp_sync_info *ldp_sync_info;
+
+	switch (args->event) {
+	case NB_EV_VALIDATE:
+	case NB_EV_PREPARE:
+	case NB_EV_ABORT:
+		break;
+	case NB_EV_APPLY:
+		circuit = nb_running_get_entry(args->dnode, NULL, true);
+		ldp_sync_info = circuit->ldp_sync_info;
+
+		UNSET_FLAG(ldp_sync_info->flags, LDP_SYNC_FLAG_HOLDDOWN);
+
+		if (circuit->area)
+			isis_if_set_ldp_sync_holddown(circuit);
+		break;
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/fast-reroute/level-1/lfa/enable
+ */
+int lib_interface_isis_fast_reroute_level_1_lfa_enable_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->lfa_protection[0] = yang_dnode_get_bool(args->dnode, NULL);
+
+	area = circuit->area;
+	if (area) {
+		if (circuit->lfa_protection[0])
+			area->lfa_protected_links[0]++;
+		else {
+			assert(area->lfa_protected_links[0] > 0);
+			area->lfa_protected_links[0]--;
+		}
+
+		lsp_regenerate_schedule(area, area->is_type, 0);
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/fast-reroute/level-1/lfa/exclude-interface
+ */
+int lib_interface_isis_fast_reroute_level_1_lfa_exclude_interface_create(
+	struct nb_cb_create_args *args)
+{
+	struct isis_area *area;
+	struct isis_circuit *circuit;
+	const char *exclude_ifname;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	exclude_ifname = yang_dnode_get_string(args->dnode, NULL);
+
+	isis_lfa_excluded_iface_add(circuit, ISIS_LEVEL1, exclude_ifname);
+	area = circuit->area;
+	if (area)
+		lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+int lib_interface_isis_fast_reroute_level_1_lfa_exclude_interface_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+	struct isis_circuit *circuit;
+	const char *exclude_ifname;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	exclude_ifname = yang_dnode_get_string(args->dnode, NULL);
+
+	isis_lfa_excluded_iface_delete(circuit, ISIS_LEVEL1, exclude_ifname);
+	area = circuit->area;
+	if (area)
+		lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/fast-reroute/level-1/remote-lfa/enable
+ */
+int lib_interface_isis_fast_reroute_level_1_remote_lfa_enable_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->rlfa_protection[0] = yang_dnode_get_bool(args->dnode, NULL);
+
+	area = circuit->area;
+	if (area) {
+		if (circuit->rlfa_protection[0])
+			area->rlfa_protected_links[0]++;
+		else {
+			assert(area->rlfa_protected_links[0] > 0);
+			area->rlfa_protected_links[0]--;
+		}
+
+		lsp_regenerate_schedule(area, area->is_type, 0);
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/fast-reroute/level-1/remote-lfa/maximum-metric
+ */
+int lib_interface_isis_fast_reroute_level_1_remote_lfa_maximum_metric_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->rlfa_max_metric[0] = yang_dnode_get_uint32(args->dnode, NULL);
+
+	area = circuit->area;
+	if (area)
+		lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+int lib_interface_isis_fast_reroute_level_1_remote_lfa_maximum_metric_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->rlfa_max_metric[0] = 0;
+
+	area = circuit->area;
+	if (area)
+		lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/fast-reroute/level-1/ti-lfa/enable
+ */
+int lib_interface_isis_fast_reroute_level_1_ti_lfa_enable_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->tilfa_protection[0] = yang_dnode_get_bool(args->dnode, NULL);
+
+	area = circuit->area;
+	if (area) {
+		if (circuit->tilfa_protection[0])
+			area->tilfa_protected_links[0]++;
+		else {
+			assert(area->tilfa_protected_links[0] > 0);
+			area->tilfa_protected_links[0]--;
+		}
+
+		lsp_regenerate_schedule(area, area->is_type, 0);
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/fast-reroute/level-1/ti-lfa/node-protection
+ */
+int lib_interface_isis_fast_reroute_level_1_ti_lfa_node_protection_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->tilfa_node_protection[0] =
+		yang_dnode_get_bool(args->dnode, NULL);
+
+	area = circuit->area;
+	if (area)
+		lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/fast-reroute/level-1/ti-lfa/link-fallback
+ */
+int lib_interface_isis_fast_reroute_level_1_ti_lfa_link_fallback_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->tilfa_link_fallback[0] =
+		yang_dnode_get_bool(args->dnode, NULL);
+
+	area = circuit->area;
+	if (area)
+		lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/fast-reroute/level-2/lfa/enable
+ */
+int lib_interface_isis_fast_reroute_level_2_lfa_enable_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->lfa_protection[1] = yang_dnode_get_bool(args->dnode, NULL);
+
+	area = circuit->area;
+	if (area) {
+		if (circuit->lfa_protection[1])
+			area->lfa_protected_links[1]++;
+		else {
+			assert(area->lfa_protected_links[1] > 0);
+			area->lfa_protected_links[1]--;
+		}
+
+		lsp_regenerate_schedule(area, area->is_type, 0);
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/fast-reroute/level-2/lfa/exclude-interface
+ */
+int lib_interface_isis_fast_reroute_level_2_lfa_exclude_interface_create(
+	struct nb_cb_create_args *args)
+{
+	struct isis_area *area;
+	struct isis_circuit *circuit;
+	const char *exclude_ifname;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	exclude_ifname = yang_dnode_get_string(args->dnode, NULL);
+
+	isis_lfa_excluded_iface_add(circuit, ISIS_LEVEL2, exclude_ifname);
+	area = circuit->area;
+	if (area)
+		lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+int lib_interface_isis_fast_reroute_level_2_lfa_exclude_interface_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+	struct isis_circuit *circuit;
+	const char *exclude_ifname;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	exclude_ifname = yang_dnode_get_string(args->dnode, NULL);
+
+	isis_lfa_excluded_iface_delete(circuit, ISIS_LEVEL2, exclude_ifname);
+	area = circuit->area;
+	if (area)
+		lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/fast-reroute/level-2/remote-lfa/enable
+ */
+int lib_interface_isis_fast_reroute_level_2_remote_lfa_enable_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->rlfa_protection[1] = yang_dnode_get_bool(args->dnode, NULL);
+
+	area = circuit->area;
+	if (area) {
+		if (circuit->rlfa_protection[1])
+			area->rlfa_protected_links[1]++;
+		else {
+			assert(area->rlfa_protected_links[1] > 0);
+			area->rlfa_protected_links[1]--;
+		}
+
+		lsp_regenerate_schedule(area, area->is_type, 0);
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/fast-reroute/level-2/remote-lfa/maximum-metric
+ */
+int lib_interface_isis_fast_reroute_level_2_remote_lfa_maximum_metric_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->rlfa_max_metric[1] = yang_dnode_get_uint32(args->dnode, NULL);
+
+	area = circuit->area;
+	if (area)
+		lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+int lib_interface_isis_fast_reroute_level_2_remote_lfa_maximum_metric_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct isis_area *area;
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->rlfa_max_metric[1] = 0;
+
+	area = circuit->area;
+	if (area)
+		lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/fast-reroute/level-2/ti-lfa/enable
+ */
+int lib_interface_isis_fast_reroute_level_2_ti_lfa_enable_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->tilfa_protection[1] = yang_dnode_get_bool(args->dnode, NULL);
+
+	area = circuit->area;
+	if (area) {
+		if (circuit->tilfa_protection[1])
+			area->tilfa_protected_links[1]++;
+		else {
+			assert(area->tilfa_protected_links[1] > 0);
+			area->tilfa_protected_links[1]--;
+		}
+
+		lsp_regenerate_schedule(area, area->is_type, 0);
+	}
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/fast-reroute/level-2/ti-lfa/node-protection
+ */
+int lib_interface_isis_fast_reroute_level_2_ti_lfa_node_protection_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->tilfa_node_protection[1] =
+		yang_dnode_get_bool(args->dnode, NULL);
+
+	area = circuit->area;
+	if (area)
+		lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}
+
+/*
+ * XPath:
+ * /frr-interface:lib/interface/frr-isisd:isis/fast-reroute/level-2/ti-lfa/link-fallback
+ */
+int lib_interface_isis_fast_reroute_level_2_ti_lfa_link_fallback_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct isis_area *area;
+	struct isis_circuit *circuit;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	circuit = nb_running_get_entry(args->dnode, NULL, true);
+	circuit->tilfa_link_fallback[1] =
+		yang_dnode_get_bool(args->dnode, NULL);
+
+	area = circuit->area;
+	if (area)
+		lsp_regenerate_schedule(area, area->is_type, 0);
+
+	return NB_OK;
+}