diff options
Diffstat (limited to 'doc/user/ipv6.rst')
| -rw-r--r-- | doc/user/ipv6.rst | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/doc/user/ipv6.rst b/doc/user/ipv6.rst new file mode 100644 index 0000000..4f01061 --- /dev/null +++ b/doc/user/ipv6.rst @@ -0,0 +1,223 @@ +.. _ipv6-support: + +************ +IPv6 Support +************ + +FRR fully supports IPv6 routing. As described so far, FRR supports RIPng, +OSPFv3, and BGP-4+. You can give IPv6 addresses to an interface and configure +static IPv6 routing information. FRR IPv6 also provides automatic address +configuration via a feature called ``address auto configuration``. To do it, +the router must send router advertisement messages to the all nodes that exist +on the network. + +Previous versions of FRR could be built without IPv6 support. This is +no longer possible. + +Router Advertisement +==================== + +.. clicmd:: show ipv6 nd ra-interfaces [vrf <VRFNAME|all>] + + Show configured route advertisement interfaces. VRF subcommand only + applicable for netns-based vrfs. + +.. clicmd:: ipv6 nd suppress-ra + + Don't send router advertisement messages. The ``no`` form of this command + enables sending RA messages. + +.. clicmd:: ipv6 nd prefix ipv6prefix [valid-lifetime] [preferred-lifetime] [off-link] [no-autoconfig] [router-address] + + Configuring the IPv6 prefix to include in router advertisements. Several prefix + specific optional parameters and flags may follow: + + - ``valid-lifetime``: the length of time in seconds during what the prefix is + valid for the purpose of on-link determination. Value ``infinite`` represents + infinity (i.e. a value of all one bits (``0xffffffff``)). + Range: ``(0-4294967295)`` Default: ``2592000`` + + - ``preferred-lifetime``: the length of time in seconds during what addresses + generated from the prefix remain preferred. Value ``infinite`` represents + infinity. + Range: ``(0-4294967295)`` Default: ``604800`` + + - ``off-link``: indicates that advertisement makes no statement about on-link or + off-link properties of the prefix. + Default: not set, i.e. this prefix can be used for on-link determination. + + - ``no-autoconfig``: indicates to hosts on the local link that the specified prefix + cannot be used for IPv6 autoconfiguration. + + Default: not set, i.e. prefix can be used for autoconfiguration. + + - ``router-address``: indicates to hosts on the local link that the specified + prefix contains a complete IP address by setting R flag. + + Default: not set, i.e. hosts do not assume a complete IP address is placed. + +.. clicmd:: ipv6 nd ra-interval [(1-1800)] + + The maximum time allowed between sending unsolicited multicast router + advertisements from the interface, in seconds. + Default: ``600`` + +.. clicmd:: ipv6 nd ra-interval [msec (70-1800000)] + + The maximum time allowed between sending unsolicited multicast router + advertisements from the interface, in milliseconds. + Default: ``600000`` + +.. clicmd:: ipv6 nd ra-fast-retrans + + RFC4861 states that consecutive RA packets should be sent no more + frequently than three seconds apart. FRR by default allows faster + transmissions of RA packets in order to speed convergence and + neighbor establishment, particularly for unnumbered peering. By + turning off ipv6 nd ra-fast-retrans, the implementation is + compliant with the RFC at the cost of slower convergence + and neighbor establishment. + Default: enabled + +.. clicmd:: ipv6 nd ra-retrans-interval [(0-4294967295)] + + The value to be placed in the retrans timer field of router advertisements + sent from the interface, in msec. Indicates the interval between router + advertisement retransmissions. Setting the value to zero indicates that + the value is unspecified by this router. Must be between zero or 4294967295 + msec. + Default: ``0`` + +.. clicmd:: ipv6 nd ra-hop-limit [(0-255)] + + The value to be placed in the hop count field of router advertisements sent + from the interface, in hops. Indicates the maximum diameter of the network. + Setting the value to zero indicates that the value is unspecified by this + router. Must be between zero or 255 hops. + Default: ``64`` + +.. clicmd:: ipv6 nd ra-lifetime [(0-9000)] + + The value to be placed in the Router Lifetime field of router advertisements + sent from the interface, in seconds. Indicates the usefulness of the router + as a default router on this interface. Setting the value to zero indicates + that the router should not be considered a default router on this interface. + Must be either zero or between value specified with ``ipv6 nd ra-interval`` + (or default) and 9000 seconds. + Default: ``1800`` + +.. clicmd:: ipv6 nd reachable-time [(1-3600000)] + + The value to be placed in the Reachable Time field in the Router + Advertisement messages sent by the router, in milliseconds. The configured + time enables the router to detect unavailable neighbors. The value zero + means unspecified (by this router). + Default: ``0`` + +.. clicmd:: ipv6 nd managed-config-flag + + Set/unset flag in IPv6 router advertisements which indicates to hosts that + they should use managed (stateful) protocol for addresses autoconfiguration + in addition to any addresses autoconfigured using stateless address + autoconfiguration. + Default: not set + +.. clicmd:: ipv6 nd other-config-flag + + Set/unset flag in IPv6 router advertisements which indicates to hosts that + they should use administered (stateful) protocol to obtain autoconfiguration + information other than addresses. + Default: not set + +.. clicmd:: ipv6 nd home-agent-config-flag + + Set/unset flag in IPv6 router advertisements which indicates to hosts that + the router acts as a Home Agent and includes a Home Agent Option. + Default: not set + + +.. clicmd:: ipv6 nd home-agent-preference [(0-65535)] + + The value to be placed in Home Agent Option, when Home Agent config flag is + set, which indicates to hosts Home Agent preference. The default value of 0 + stands for the lowest preference possible. + Default: ``0`` + +.. clicmd:: ipv6 nd home-agent-lifetime [(0-65520)] + + The value to be placed in Home Agent Option, when Home Agent config flag is set, + which indicates to hosts Home Agent Lifetime. The default value of 0 means to + place the current Router Lifetime value. + + Default: ``0`` + +.. clicmd:: ipv6 nd adv-interval-option + + Include an Advertisement Interval option which indicates to hosts the maximum time, + in milliseconds, between successive unsolicited Router Advertisements. + Default: not set + +.. clicmd:: ipv6 nd router-preference [(high|medium|low)] + + Set default router preference in IPv6 router advertisements per RFC4191. + Default: medium + +.. clicmd:: ipv6 nd mtu [(1-65535)] + + Include an MTU (type 5) option in each RA packet to assist the attached + hosts in proper interface configuration. The announced value is not verified + to be consistent with router interface MTU. + + Default: don't advertise any MTU option. + +.. clicmd:: ipv6 nd rdnss ipv6address [lifetime] + + Recursive DNS server address to advertise using the RDNSS (type 25) option + described in RFC8106. Can be specified more than once to advertise multiple + addresses. Note that hosts may choose to limit the number of RDNSS addresses + to track. + + Optional parameter: + + - ``lifetime``: the maximum time in seconds over which the specified address + may be used for domain name resolution. Value ``infinite`` represents + infinity (i.e. a value of all one bits (``0xffffffff``)). A value of 0 + indicates that the address must no longer be used. + Range: ``(0-4294967295)`` Default: ``3 * ra-interval`` + + Default: do not emit RDNSS option + +.. clicmd:: ipv6 nd dnssl domain-name-suffix [lifetime] + + Advertise DNS search list using the DNSSL (type 31) option described in + RFC8106. Specify more than once to advertise multiple domain name suffixes. + Host implementations may limit the number of honored search list entries. + + Optional parameter: + + - ``lifetime``: the maximum time in seconds over which the specified domain + suffix may be used in the course of name resolution. Value ``infinite`` + represents infinity (i.e. a value of all one bits (``0xffffffff``)). A + value of 0 indicates that the name suffix must no longer be used. + Range: ``(0-4294967295)`` Default: ``3 * ra-interval`` + + Default: do not emit DNSSL option + +Router Advertisement Configuration Example +========================================== +A small example: + +.. code-block:: frr + + interface eth0 + no ipv6 nd suppress-ra + ipv6 nd prefix 2001:0DB8:5009::/64 + + +.. seealso:: + + - :rfc:`2462` (IPv6 Stateless Address Autoconfiguration) + - :rfc:`4861` (Neighbor Discovery for IP Version 6 (IPv6)) + - :rfc:`6275` (Mobility Support in IPv6) + - :rfc:`4191` (Default Router Preferences and More-Specific Routes) + - :rfc:`8106` (IPv6 Router Advertisement Options for DNS Configuration) |