Users Guide

Congure the following parameters:
• ip-address or peer-group-name: enter the neighbor’s IP address or the peer group’s name.
• map-name: enter the name of a congured route map.
• in: apply the route map to inbound routes.
• out: apply the route map to outbound routes.
To view the BGP conguration, use the show config command in CONFIGURATION ROUTER BGP mode. To view a route map
conguration, use the show route-map command in EXEC Privilege mode.
Filtering BGP Routes Using AS-PATH Information
To lter routes based on AS-PATH information, use these commands.
1 Create a AS-PATH ACL and assign it a name.
CONFIGURATION mode
ip as-path access-list as-path-name
2 Create a AS-PATH ACL lter with a deny or permit action.
AS-PATH ACL mode
{deny | permit} as-regular-expression
3 Return to CONFIGURATION mode.
AS-PATH ACL
exit
4 Enter ROUTER BGP mode.
CONFIGURATION mode
router bgp as-number
5 Filter routes based on the criteria in the congured route map.
CONFIG-ROUTER-BGP mode
neighbor {ip-address | peer-group-name} filter-list as-path-name {in | out}
Congure the following parameters:
• ip-address or peer-group-name: enter the neighbor’s IP address or the peer group’s name.
• as-path-name: enter the name of a congured AS-PATH ACL.
• in: apply the AS-PATH ACL map to inbound routes.
• out: apply the AS-PATH ACL to outbound routes.
To view which commands are congured, use the show config command in CONFIGURATION ROUTER BGP mode and the show ip
as-path-access-list command in EXEC Privilege mode.
To forward all routes not meeting the AS-PATH ACL criteria, include the permit .* lter in your AS-PATH ACL.
Conguring BGP Route Reectors
BGP route reectors are intended for ASs with a large mesh; they reduce the amount of BGP control trac.
NOTE
: Dell Networking recommends not using multipath and add path simultaneously in a route reector.
With route reection congured properly, IBGP routers are not fully meshed within a cluster but all receive routing information.
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Border Gateway Protocol IPv4 (BGPv4)