Concept Guide

Example of Using Regular Expression to Filter AS Paths
DellEMC(config)#router bgp 99
DellEMC(conf-router_bgp)#neigh AAA peer-group
DellEMC(conf-router_bgp)#neigh AAA no shut
DellEMC(conf-router_bgp)#show conf
!
router bgp 99
neighbor AAA peer-group
neighbor AAA no shutdown
neighbor 10.155.15.2 remote-as 32
neighbor 10.155.15.2 shutdown
DellEMC(conf-router_bgp)#neigh 10.155.15.2 filter-list 1 in
DellEMC(conf-router_bgp)#ex
DellEMC(conf)#ip as-path access-list Eagle
DellEMC(config-as-path)#deny 32$
DellEMC(config-as-path)#ex
DellEMC(conf)#router bgp 99
DellEMC(conf-router_bgp)#neighbor AAA filter-list Eagle in
DellEMC(conf-router_bgp)#show conf
!
router bgp 99
neighbor AAA peer-group
neighbor AAA filter-list Eaglein
neighbor AAA no shutdown
neighbor 10.155.15.2 remote-as 32
neighbor 10.155.15.2 filter-list 1 in
neighbor 10.155.15.2 shutdown
DellEMC(conf-router_bgp)#ex
DellEMC(conf)#ex
DellEMC#show ip as-path-access-lists
ip as-path access-list Eagle
deny 32$
DellEMC#
Redistributing Routes
In addition to ltering routes, you can add routes from other routing instances or protocols to the BGP process. You can congure the
device to redistribute ISIS, OSPF, static, or directly connected routes into BGP process using the
redistribute command.
To add routes from other routing instances or protocols, use any of the following commands in ROUTER BGP mode.
• Include directly connected or user-congured (static) routes into BGP.
ROUTER BGP or CONF-ROUTER_BGPv6_ AF mode
redistribute {connected | static} [route-map map-name]
Congure the following parameters:
– connected: Indicate that you are redistributing routes to directly connected routes into BGP.
– static: Indicate that you are redistributing static routes into BGP.
– route-map map-name: Specify the name of a congured route map to be consulted before adding the connected or static
route.
• Include specic ISIS routes into BGP.
ROUTER BGP or CONF-ROUTER_BGPv6_ AF mode
redistribute isis [level-1 | level-1-2 | level-2] [metric value] [route-map map-name]
Congure the following parameters:
– isis: Indicate that you are redistributing ISIS routes into BGP.
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BGP IP version 4 (BGPv4) Overview