diff options
| -rw-r--r-- | doc/bird.sgml | 94 |
1 files changed, 83 insertions, 11 deletions
diff --git a/doc/bird.sgml b/doc/bird.sgml index c549e3c3..129e9c08 100644 --- a/doc/bird.sgml +++ b/doc/bird.sgml @@ -3336,7 +3336,8 @@ time intervals or as an answer to a request) advertisement packets to connected networks. These packets contain basic information about a local network (e.g. a list of network prefixes), which allows network hosts to autoconfigure network addresses and choose a default route. BIRD implements router behavior as defined -in <rfc id="4861"> and also the DNS extensions from <rfc id="6106">. +in <rfc id="4861">, router preferences and specific routes (<rfc id="4191">), +and DNS extensions (<rfc id="6106">). <sect1>Configuration <label id="radv-config"> @@ -3373,7 +3374,7 @@ definitions, prefix definitions and DNS definitions: definitions may also be interface-specific when used inside interface options. By default, interface uses both global and interface-specific options, but that can be changed by <cf/rdnss local/ option. -dsc-iface + <tag><label id="radv-dnssl">dnssl { <m/options/ }</tag> DNSSL definitions allow to specify a list of advertised DNS search domains together with their options. Like <cf/rdnss/ above, multiple @@ -3398,6 +3399,18 @@ dsc-iface default router. <cf/preferred lifetime/ and <cf/valid lifetime/ could also be configured as <cf/sensitive/ for a prefix, which would cause autoconfigured IPs to be deprecated or even removed. + + <tag><label id="radv-propagate-routes">propagate routes <m/switch/</tag> + This option controls propagation of more specific routes, as defined in + <rfc id="4191">. If enabled, all routes exported to the RAdv protocol, + with the exception of the trigger prefix, are added to advertisments as + additional options. The lifetime and preference of advertised routes can + be set individually by <cf/ra_lifetime/ and <cf/ra_preference/ route + attributes, or per interface by <cf/route lifetime/ and + <cf/route preference/ options. Default: disabled. + + Note that the RFC discourages from sending more than 17 routes and + recommends the routes to be configured manually. </descrip> <p>Interface specific options: @@ -3444,21 +3457,45 @@ dsc-iface hosts. Valid values are 0-255, 0 means unspecified. Default: 64 <tag><label id="radv-iface-default-lifetime">default lifetime <m/expr/ [sensitive <m/switch/]</tag> - This option specifies the time (in seconds) how long (after the receipt + This option specifies the time (in seconds) how long (since the receipt of RA) hosts may use the router as a default router. 0 means do not use as a default router. For <cf/sensitive/ option, see <ref id="radv-trigger" name="trigger">. Default: 3 * <cf/max ra interval/, <cf/sensitive/ yes. - <tag><label id="radv-iface-linger-time">linger time <m/expr/</tag> - When a prefix disappears, it is advertised for some time with 0 - lifetime, to inform clients the prefix is no longer usable. This option - sets the time for how long it is advertised (in seconds). Maximum is - 3600, 0 means disabled. Default: 300. - - <tag><label id="radv-iface-default-preference-low">default preference low|medium|high</tag> + <tag><label id="radv-iface-default-preference">default preference low|medium|high</tag> This option specifies the Default Router Preference value to advertise to hosts. Default: medium. + <tag><label id="radv-iface-route-lifetime">route lifetime <m/expr/ [sensitive <m/switch/]</tag> + This option specifies the default value of advertised lifetime for + specific routes; i.e., the time (in seconds) for how long (since the + receipt of RA) hosts should consider these routes valid. A special value + 0xffffffff represents infinity. The lifetime can be overriden on a per + route basis by the <ref id="rta-ra-lifetime" name="ra_lifetime"> route + attribute. Default: 3 * <cf/max ra interval/, <cf/sensitive/ no. + + For the <cf/sensitive/ option, see <ref id="radv-trigger" name="trigger">. + If <cf/sensitive/ is enabled, even the routes with the <cf/ra_lifetime/ + attribute become sensitive to the trigger. + + <tag><label id="radv-iface-route-preference">route preference low|medium|high</tag> + This option specifies the default value of advertised route preference + for specific routes. The value can be overriden on a per route basis by + the <ref id="rta-ra-preference" name="ra_preference"> route attribute. + Default: medium. + + <tag><label id="radv-prefix-linger-time">prefix linger time <m/expr/</tag> + When a prefix or a route disappears, it is advertised for some time with + zero lifetime, to inform clients it is no longer valid. This option + specifies the time (in seconds) for how long prefixes are advertised + that way. Default: 3 * <cf/max ra interval/. + + <tag><label id="radv-route-linger-time">route linger time <m/expr/</tag> + When a prefix or a route disappears, it is advertised for some time with + zero lifetime, to inform clients it is no longer valid. This option + specifies the time (in seconds) for how long routes are advertised + that way. Default: 3 * <cf/max ra interval/. + <tag><label id="radv-iface-rdnss-local">rdnss local <m/switch/</tag> Use only local (interface-specific) RDNSS definitions for this interface. Otherwise, both global and local definitions are used. Could @@ -3505,7 +3542,6 @@ dsc-iface <cf/sensitive/ no. </descrip> - <p>RDNSS specific options: <descrip> @@ -3538,12 +3574,48 @@ dsc-iface RDNSS <cf/lifetime/ option above. Default: 3 * <cf/max ra interval/. </descrip> +<sect1>Attributes +<label id="radv-attr"> + +<p>RAdv defines two route attributes: + +<descrip> + <tag><label id="rta-ra-preference">enum ra_preference/</tag> + The preference of the route. The value can be <it/RA_PREF_LOW/, + <it/RA_PREF_MEDIUM/ or <it/RA_PREF_HIGH/. If the attribute is not set, + the <ref id="radv-iface-route-preference" name="route preference"> + option is used. + + <tag><label id="rta-ra-lifetime">int ra_lifetime/</tag> + The advertised lifetime of the route, in seconds. The special value of + 0xffffffff represents infinity. If the attribute is not set, the + <ref id="radv-iface-route-lifetime" name="route lifetime"> + option is used. +</descrip> <sect1>Example <label id="radv-exam"> <p><code> +table radv_routes; # Manually configured routes go here + +protocol static { + table radv_routes; + + route 2001:0DB8:4000::/48 unreachable; + route 2001:0DB8:4010::/48 unreachable; + + route 2001:0DB8:4020::/48 unreachable { + ra_preference = RA_PREF_HIGH; + ra_lifetime = 3600; + }; +} + protocol radv { + propagate routes yes; # Propagate the routes from the radv_routes table + table radv_routes; + export all; + interface "eth2" { max ra interval 5; # Fast failover with more routers managed yes; # Using DHCPv6 on eth2 |