Adding upstream version 2:4.20.0+dfsg.upstream/2%4.20.0+dfsg

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

1 files changed, 254 insertions, 0 deletions

diff --git a/ctdb/config/statd-callout b/ctdb/config/statd-callout
new file mode 100755
index 0000000..38c155e
--- /dev/null
+++ b/ctdb/config/statd-callout
@@ -0,0 +1,254 @@
+#!/bin/sh
+
+# This must run as root as CTDB tool commands need to access CTDB socket
+[ "$(id -u)" -eq 0 ] || exec sudo "$0" "$@"
+
+# statd must be configured to use this script as its high availability call-out.
+#
+# In most Linux versions this can be done using something like the following...
+#
+# /etc/sysconfig/nfs (Red Hat) or /etc/default/nfs-common (Debian):
+#   NFS_HOSTNAME=myhostname
+#   STATD_HOSTNAME="${NFS_HOSTNAME} -H /etc/ctdb/statd-callout"
+#
+# Newer Red Hat Linux variants instead use /etc/nfs.conf:
+#   [statd]
+#     name = myhostname
+#     ha-callout = /etc/ctdb/statd-callout
+
+[ -n "$CTDB_BASE" ] || \
+	CTDB_BASE=$(d=$(dirname "$0") && cd -P "$d" && echo "$PWD")
+
+. "${CTDB_BASE}/functions"
+
+# Overwrite this so we get some logging
+die ()
+{
+    script_log "statd-callout" "$@"
+    exit 1
+}
+
+# Try different variables to find config file for NFS_HOSTNAME
+load_system_config "nfs" "nfs-common"
+
+# If NFS_HOSTNAME not set then try to pull it out of /etc/nfs.conf
+if [ -z "$NFS_HOSTNAME" ]; then
+	if type nfsconf >/dev/null 2>&1; then
+		NFS_HOSTNAME=$(nfsconf --get statd name)
+	elif type git >/dev/null 2>&1; then
+		# git to the rescue!
+		NFS_HOSTNAME=$(git config --file=/etc/nfs.conf statd.name)
+	fi
+fi
+
+[ -n "$NFS_HOSTNAME" ] || \
+    die "NFS_HOSTNAME is not configured. statd-callout failed"
+
+############################################################
+
+ctdb_setup_state_dir "service" "nfs"
+
+# script_state_dir set by ctdb_setup_state_dir()
+# shellcheck disable=SC2154
+d="${script_state_dir}/statd-callout"
+
+mkdir -p "$d" || die "Failed to create directory \"${d}\""
+cd "$d" || die "Failed to change directory to \"${d}\""
+
+pnn=$(ctdb_get_pnn)
+
+############################################################
+
+send_notifies ()
+{
+	_smnotify="${CTDB_HELPER_BINDIR}/smnotify"
+
+	# State must monotonically increase, across the entire
+	# cluster.  Use seconds since epoch and hope the time is in
+	# sync across nodes.  Even numbers mean service is shut down,
+	# odd numbers mean service is started.
+
+	# Intentionally round to an even number
+	# shellcheck disable=SC2017
+	_state_even=$(( $(date '+%s') / 2 * 2))
+
+	_prev=""
+	while read _sip _cip ; do
+		# NOTE: Consider optimising smnotify to read all the
+		# data from stdin and then run it in the background.
+
+		# Reset stateval for each serverip
+		if [ "$_sip" != "$_prev" ] ; then
+			_stateval="$_state_even"
+		fi
+
+		# Send notifies for server shutdown
+		"$_smnotify" --client="$_cip" --ip="$_sip" \
+			     --server="$_sip" --stateval="$_stateval"
+		"$_smnotify" --client="$_cip" --ip="$_sip" \
+			     --server="$NFS_HOSTNAME" --stateval="$_stateval"
+
+		# Send notifies for server startup
+		_stateval=$((_stateval + 1))
+		"$_smnotify" --client="$_cip" --ip="$_sip" \
+			     --server="$_sip" --stateval="$_stateval"
+		"$_smnotify" --client="$_cip" --ip="$_sip" \
+			     --server="$NFS_HOSTNAME" --stateval="$_stateval"
+	done
+}
+
+delete_records ()
+{
+	while read _sip _cip ; do
+		_key="statd-state@${_sip}@${_cip}"
+		echo "\"${_key}\" \"\""
+	done | $CTDB ptrans "ctdb.tdb"
+}
+
+############################################################
+
+case "$1" in
+    # Keep a single file to keep track of the last "add-client" or
+    # "del-client'.  These get pushed to ctdb.tdb during "update",
+    # which will generally be run once each "monitor" cycle.  In this
+    # way we avoid scalability problems with flood of persistent
+    # transactions after a "notify" when all the clients re-take their
+    # locks.
+
+    add-client)
+	# statd does not tell us to which IP the client connected so
+	# we must add it to all the IPs that we serve
+	cip="$2"
+	date=$(date '+%s')
+	# x is intentionally ignored
+	# shellcheck disable=SC2034
+	$CTDB ip -X |
+	tail -n +2 |
+	while IFS="|" read x sip node x ; do
+	    [ "$node" = "$pnn" ] || continue # not us
+	    key="statd-state@${sip}@${cip}"
+	    echo "\"${key}\" \"${date}\"" >"$key"
+	done
+	;;
+
+    del-client)
+	# statd does not tell us from which IP the client disconnected
+	# so we must add it to all the IPs that we serve
+	cip="$2"
+	# x is intentionally ignored
+	# shellcheck disable=SC2034
+	$CTDB ip -X |
+	tail -n +2 |
+	while IFS="|" read x sip node x ; do
+	    [ "$node" = "$pnn" ] || continue # not us
+	    key="statd-state@${sip}@${cip}"
+	    echo "\"${key}\" \"\"" >"$key"
+	done
+	;;
+
+    update)
+        files=$(echo statd-state@*)
+	if [ "$files" = "statd-state@*" ] ; then
+	    # No files!
+	    exit 0
+	fi
+	# Filter out lines for any IP addresses that are not currently
+	# hosted public IP addresses.
+	ctdb_ips=$($CTDB ip | tail -n +2)
+	sed_expr=$(echo "$ctdb_ips" |
+	    awk -v pnn="$pnn" 'pnn == $2 {
+                ip = $1; gsub(/\./, "\\.", ip);
+                printf "/statd-state@%s@/p\n", ip }')
+	# Intentional multi-word expansion for multiple files
+	# shellcheck disable=SC2086
+	items=$(sed -n "$sed_expr" $files)
+	if [ -n "$items" ] ; then
+		if echo "$items"  | $CTDB ptrans "ctdb.tdb" ; then
+			# shellcheck disable=SC2086
+			rm $files
+		fi
+	fi
+	;;
+
+    notify)
+	# we must restart the lockmanager (on all nodes) so that we get
+	# a clusterwide grace period (so other clients don't take out
+	# conflicting locks through other nodes before all locks have been
+	# reclaimed)
+
+	# we need these settings to make sure that no tcp connections survive
+	# across a very fast failover/failback
+	#echo 10 > /proc/sys/net/ipv4/tcp_fin_timeout
+	#echo 0 > /proc/sys/net/ipv4/tcp_max_tw_buckets
+	#echo 0 > /proc/sys/net/ipv4/tcp_max_orphans
+
+	# Delete the notification list for statd, we don't want it to 
+	# ping any clients
+	rm -f /var/lib/nfs/statd/sm/*
+	rm -f /var/lib/nfs/statd/sm.bak/*
+
+	# We must also let some time pass between stopping and
+	# restarting the lock manager.  Otherwise there is a window
+	# where the lock manager will respond "strangely" immediately
+	# after restarting it, which causes clients to fail to reclaim
+	# their locks.
+	nfs_callout_init
+	"$CTDB_NFS_CALLOUT" "stop" "nlockmgr" >/dev/null 2>&1
+        sleep 2
+	"$CTDB_NFS_CALLOUT" "start" "nlockmgr" >/dev/null 2>&1
+
+	# we now need to send out additional statd notifications to ensure
+	# that clients understand that the lockmanager has restarted.
+	# we have three cases:
+	# 1, clients that ignore the ip address the stat notification came from
+	#    and ONLY care about the 'name' in the notify packet.
+	#    these clients ONLY work with lock failover IFF that name
+	#    can be resolved into an ipaddress that matches the one used
+	#    to mount the share.  (==linux clients)
+	#    This is handled when starting lockmanager above,  but those
+	#    packets are sent from the "wrong" ip address, something linux
+	#    clients are ok with, buth other clients will barf at.
+	# 2, Some clients only accept statd packets IFF they come from the
+	#    'correct' ip address.
+	# 2a,Send out the notification using the 'correct' ip address and also
+	#    specify the 'correct' hostname in the statd packet.
+	#    Some clients require both the correct source address and also the
+	#    correct name. (these clients also ONLY work if the ip addresses
+	#    used to map the share can be resolved into the name returned in
+	#    the notify packet.)
+	# 2b,Other clients require that the source ip address of the notify
+	#    packet matches the ip address used to take out the lock.
+	#    I.e. that the correct source address is used.
+	#    These clients also require that the statd notify packet contains
+	#    the name as the ip address used when the lock was taken out.
+	#
+	# Both 2a and 2b are commonly used in lockmanagers since they maximize
+	# probability that the client will accept the statd notify packet and
+	# not just ignore it.
+	# For all IPs we serve, collect info and push to the config database
+
+	# Construct a sed expression to take catdb output and produce pairs of:
+	#   server-IP client-IP
+	# but only for the server-IPs that are hosted on this node.
+	ctdb_all_ips=$($CTDB ip all | tail -n +2)
+	sed_expr=$(echo "$ctdb_all_ips" |
+	    awk -v pnn="$pnn" 'pnn == $2 {
+                ip = $1; gsub(/\./, "\\.", ip);
+                printf "s/^key.*=.*statd-state@\\(%s\\)@\\([^\"]*\\).*/\\1 \\2/p\n", ip }')
+
+	statd_state=$($CTDB catdb ctdb.tdb | sed -n "$sed_expr" | sort)
+	[ -n "$statd_state" ] || exit 0
+
+	echo "$statd_state" | send_notifies
+	echo "$statd_state" | delete_records
+
+	# Remove any stale touch files (i.e. for IPs not currently
+	# hosted on this node and created since the last "update").
+	# There's nothing else we can do with them at this stage.
+	echo "$ctdb_all_ips" |
+	    awk -v pnn="$pnn" 'pnn != $2 { print $1 }' |
+	    while read sip ; do
+		rm -f "statd-state@${sip}@"*
+	    done
+	;;
+esac