// This is an example configuration file for DHCPv6 server in Kea.
// It attempts to showcase some of the more advanced features.
// Topology wise, it's a basic scenario with one IPv6 subnet configured.
// It is assumed that one subnet (2001:db8:1::/64) is available directly
// over eth0 interface.
//
// The following features are currently showcased here:
// 1. Configuration of MAC/hardware address sources in DHCPv6
// 2. RSOO (Relay supplied options) - Some relays may insert options with the
//    intention for the server to insert them into client directed messages.
// 3. Control socket. Kea can open a socket and listen for incoming
//    commands.

{ "Dhcp6":

{
    // Kea is told to listen on eth0 network interface only.
    "interfaces-config": {
        "interfaces": [ "eth0" ],

        // This makes interfaces to be re-detected at each (re-)configuration.
        // By default it is true.
        "re-detect": true
    },

    // We need to specify the database used to store leases. As of
    // June 2022, three database backends are supported: MySQL,
    // PostgreSQL and the in-memory database, Memfile.
    // We will use memfile because it doesn't require any prior set up.
    "lease-database": {
        "type": "memfile",
        "lfc-interval": 3600
    },

     "sanity-checks": {
        // This parameter determines what to do when a new lease appears in the
        // system (i.e. either is read from disk during memfile startup or is
        // added via lease commands). There are five modes supported:
        // none - do nothing, accept them as is
        // warn - if subnet-id problems are detected, print a warning, but
        //        otherwise load the lease as is. This is the default value.
        // fix - attempt to fix the lease by finding appropriate subnet-id value.
        //       if there is no suitable subnet, the lease is loaded as is.
        // fix-del - attempt to fix the lease by finding appropriate subnet-id
        //           value. If there is no suitable subnet, the lease is deleted.
        // del - delete leases that have incorrect subnet-id values.
        "lease-checks": "fix-del"
    },

    // Kea 0.9.1 introduced MAC/hardware addresses support in DHCPv6. There is
    // no single reliable method of getting MAC address information in DHCPv6.
    // Kea supports several methods. Depending on your network set up, some
    // methods may be more preferable than others, hence the configuration
    // parameter. 'mac-sources' is a list of methods. Allowed parameters are:
    // any, raw, duid, ipv6-link-local, client-link-addr-option, rfc6939 (which
    // is an alias for client-link-addr-option), remote-id, rfc4649 (which is an
    // alias for remote-id, subscriber-id, rfc4580 (which is an alias for
    // subscriber-id) and docsis.

    // Note that the order matters. Methods are attempted one by one in the
    // order specified until hardware address is obtained. If you don't care
    // which method is used, using 'any' is marginally faster than enumerating
    // them all.

    // If mac-sources are not specified, a default value of 'any' is used.
    "mac-sources": [ "client-link-addr-option", "duid", "ipv6-link-local" ],

    // RFC6422 defines a mechanism called relay-supplied options option. The
    // relay agent may insert certain options that the server will echo back to
    // the client, if certain criteria are met. One condition is that the option
    // must be RSOO-enabled (i.e. allowed to be echoed back). IANA maintains a
    // list of those options here:
    // http://www.iana.org/assignments/dhcpv6-parameters/dhcpv6-parameters.xhtml#options-relay-supplied
    // However, it is possible to allow the server to echo back additional
    // options.  This entry marks options 110, 120 and 130 as RSOO-enabled.
    "relay-supplied-options": [ "110", "120", "130" ],

    // This defines a control socket. If defined, Kea will open a UNIX socket
    // and will listen for incoming commands. See section 15 of the Kea User's
    // Guide for list of supported commands.
    "control-socket": {
        "socket-type": "unix",
        "socket-name": "/tmp/kea6-ctrl-socket"
    },

    // Addresses will be assigned with preferred and valid lifetimes
    // being 3000 and 4000, respectively. Client is told to start
    // renewing after 1000 seconds. If the server does not respond
    // after 2000 seconds since the lease was granted, client is supposed
    // to start REBIND procedure (emergency renewal that allows switching
    // to a different server).
    "preferred-lifetime": 3000,
    "valid-lifetime": 4000,
    "renew-timer": 1000,
    "rebind-timer": 2000,

    // The following list defines subnets. Each subnet consists of at
    // least subnet and pool entries. Note the user-context being
    // used throughout the definitions. This is something that is not
    // being used by Kea, it's simply parsed and stored in appropriate
    // structures. You can put anything you want in the user-context
    // as long as it is a valid JSON and it starts with a map (i.e.
    // is enclosed by curly brackets).
    // A comment entry is translated into a user-context with a
    // "comment" property so you can include comments inside the
    // configuration itself.
    "subnet6": [
    {
        "pools": [
            {
                "pool": "2001:db8:1::/80",

                // This is user context specified for this particular
                // pool. You can use it to describe the pool in some way.
                // Just keep in mind that the structure will not be used
                // by Kea itself. It will be made available to hooks if
                // they want to use it.
                "user-context": { "department": "engineering" }
            }],

        // Here's the user-context for the whole subnet.
        "user-context": { "comment": "Floor one, west wing" },
        // Equivalent using smart parser
        // "comment": "Floor one, west wing",

        // This defines PD (prefix delegation) pools. In this case
        // we have only one pool. That consists of /64 prefixes
        // being delegated out of large /48 pool. Each delegated
        // prefix will contain an excluded-prefix option.
        "pd-pools": [
        {
            "prefix": "2001:db8:abcd::",
            "prefix-len": 48,
            "delegated-len": 64,
            "excluded-prefix": "2001:db8:abcd:0:1234::",
            "excluded-prefix-len": 80,

            // Another user-context for this PD pool. Again, you can put
            // anything you want in there as long as it's valid JSON and
            // starts with a map.
            "user-context": {
                "purpose": "For CPE devices"
            }
        }
        ], // end of pools

        "id": 1,
        "subnet": "2001:db8:1::/64",
        "interface": "eth0",

        // Sometimes the relay may use an odd IPv6 address that's not matching
        // the subnet. This is discouraged, but there are valid cases when it
        // makes sense. One case is when the relay has only link-local address
        // and another is when there is a shared subnet scenario.
        "relay": {
            "ip-address": "3000::1"
        }
    }
    ],

// The following configures logging. It assumes that messages with at
// least informational level (info, warn, error and fatal) should be
// logged to stdout.
    "loggers": [
        {
            "name": "kea-dhcp6",
            "output-options": [
                {
                    "output": "stdout",
                    // Several additional parameters are possible in addition
                    // to the typical output. Flush determines whether logger
                    // flushes output to a file. Maxsize determines maximum
                    // filesize before the file is rotated. maxver
                    // specifies the maximum number of rotated files being
                    // kept.
                    "flush": true,
                    "maxsize": 204800,
                    "maxver": 4,
                    // We use pattern to specify custom log message layout
                    "pattern": "%d{%y.%m.%d %H:%M:%S.%q} %-5p [%c/%i] %m\n"
                }
            ],
            "debuglevel": 0,
            "severity": "INFO"
        }
    ]
}

}