diff options
Diffstat (limited to 'doc/bird.sgml')
| -rw-r--r-- | doc/bird.sgml | 18 |
1 files changed, 11 insertions, 7 deletions
diff --git a/doc/bird.sgml b/doc/bird.sgml index bcf1c8fb..fc5fc9ae 100644 --- a/doc/bird.sgml +++ b/doc/bird.sgml @@ -1804,13 +1804,17 @@ using the following configuration parameters: other means. Default: 0 (no local AS number allowed). <tag>enable route refresh <m/switch/</tag> - When BGP speaker changes its import filter, it has to re-examine all - routes received from its neighbor against the new filter. As these - routes might not be available, there is a BGP protocol extension Route - Refresh (specified in RFC 2918) that allows BGP speaker to request - re-advertisement of all routes from its neighbor. This option specifies - whether BIRD advertises this capability and accepts such requests. Even - when disabled, BIRD can send route refresh requests. Default: on. + After the initial route exchange, BGP protocol uses incremental updates + to keep BGP speakers synchronized. Sometimes (e.g., if BGP speaker + changes its import filter, or if there is suspicion of inconsistency) it + is necessary to do a new complete route exchange. BGP protocol extension + Route Refresh (RFC 2918) allows BGP speaker to request re-advertisement + of all routes from its neighbor. BGP protocol extension Enhanced Route + Refresh (RFC 7313) specifies explicit begin and end for such exchanges, + therefore the receiver can remove stale routes that were not advertised + during the exchange. This option specifies whether BIRD advertises these + capabilities and supports related procedures. Note that even when + disabled, BIRD can send route refresh requests. Default: on. <tag>graceful restart <m/switch/|aware</tag> When a BGP speaker restarts or crashes, neighbors will discard all |