diff options
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/bird.sgml | 24 |
1 files changed, 19 insertions, 5 deletions
diff --git a/doc/bird.sgml b/doc/bird.sgml index bde825c3..04f9258b 100644 --- a/doc/bird.sgml +++ b/doc/bird.sgml @@ -794,11 +794,13 @@ inherited from templates can be updated by new definitions. <tag><label id="proto-import">import all | none | filter <m/name/ | filter { <m/filter commands/ } | where <m/boolean filter expression/</tag> Specify a filter to be used for filtering routes coming from the protocol to the routing table. <cf/all/ is for keeping all routes, - <cf/none/ is for dropping all routes. Default: <cf/all/. + <cf/none/ is for dropping all routes. Default: <cf/all/ (except for + EBGP). <tag><label id="proto-export">export <m/filter/</tag> This is similar to the <cf>import</cf> keyword, except that it works in - the direction from the routing table to the protocol. Default: <cf/none/. + the direction from the routing table to the protocol. Default: <cf/none/ + (except for EBGP). <tag><label id="proto-import-keep-filtered">import keep filtered <m/switch/</tag> Usually, if an import filter rejects a route, the route is forgotten. @@ -866,10 +868,12 @@ template bgp { ipv4 { table mytable4; import filter { ... }; + export none; }; ipv6 { table mytable6; import filter { ... }; + export none; }; } @@ -2073,6 +2077,7 @@ avoid routing loops. <item> <rfc id="7947"> - Internet Exchange BGP Route Server <item> <rfc id="8092"> - BGP Large Communities Attribute <item> <rfc id="8203"> - BGP Administrative Shutdown Communication +<item> <rfc id="8212"> - Default EBGP Route Propagation Behavior without Policies </itemize> <sect1>Route selection rules @@ -2459,6 +2464,12 @@ together with their appropriate channels follows. </tabular> </table> +<p>Due to <rfc id="8212">, external BGP protocol requires explicit configuration +of import and export policies (in contrast to other protocols, where default +policies of <cf/import all/ and <cf/export none/ are used in absence of explicit +configuration). Note that blanket policies like <cf/all/ or <cf/none/ can still +be used in explicit configuration. + <p>BGP channels have additional config options (together with the common ones): <descrip> @@ -3631,13 +3642,13 @@ protocol kernel kern2 { } protocol bgp bgp1 { # The outside connections - ipv4 { table as1; export all; }; + ipv4 { table as1; import all; export all; }; local as 1; neighbor 192.168.0.1 as 1001; } protocol bgp bgp2 { - ipv4 { table as2; export all; }; + ipv4 { table as2; import all; export all; }; local as 2; neighbor 10.0.0.1 as 1002; } @@ -4419,7 +4430,10 @@ protocol bgp { debug all; local as 65000; neighbor 192.168.2.1 as 65001; - ipv4 { import filter peer_in_v4; }; + ipv4 { + import filter peer_in_v4; + export none; + }; } </code> |