D-Link DXS-5000-54S Emulator - Page 692

5000 Series Layer 2/3 Managed Data Center Switch CLI Reference Guide To prepend one or more AS numbers to the AS-PATH in a BGP route, use the set as-path command in Route Map Configuration mode. This command is normally used to insert one or more instances of the local AS number at the beginning of the AS_PATH attribute of a BGP route. Doing so increases the ASPATH length of the route. The AS-PATH length has a strong influence on BGP route selection. Changing the AS-PATH length can influence route selection on the local router or on routers to which the route is advertised. When prepending an inbound route, if the first segment in the AS_PATH of the received route is an AS_SEQUENCE, as-path-string is inserted at the beginning of the sequence. If the first segment is an AS_SET, as-path-string is added as a new segment with type AS_SEQUENCE at the beginning of the AS-PATH. When prepending an outbound route to an external peer, as-path-string follows the local AS number, which is always the first ASN. No command removes a set command from a route map. set as-path prepend as-path-string no set as-path prepend as-path-string Parameters as-path-string List of AS-PATH numbers to insert at the beginning of the AS_PATH attribute of matching BGP routes. To prepend more than one AS number, separate the ASNs with a space and enclose the string in quotes. Up to ten AS numbers may be prepended. Default The default is None. Command Mode Route Map Config Example The following example prepends three instances an external peer's AS number to paths received from that peer, making routes learned from this peer less likely to be chosen as the best path. (Routing)#config (Routing)#route-map ppAsPath (Routing)#set as-path prepend "2 2 2" (Routing)#exit (Routing)#router bgp 1 (Routing)#neighbor 172.20.1.2 remote-as 2 (Routing)#neighbor 172.20.1.2 route-map ppAsPath in 7-63 set comm-list delete To remove BGP communities from an inbound or outbound UPDATE message, use the set comm-list delete command in Route Map Configuration mode. A route map with this set command can be used to remove selected communities from inbound and outbound routes. When a community list is applied to a route for this purpose, each of the route's communities is submitted to the community list one at a time. Communities permitted by the list are removed from the route. Because communities are processed 686