Concept Guide

By default, all peer groups are disabled.
4 Create a BGP neighbor.
CONFIG-ROUTER-BGP mode
neighbor {ip-address | ipv6-address} remote-as as-number
5 Enable the neighbor.
CONFIG-ROUTER-BGP mode
neighbor {ip-address | ipv6-address} no shutdown
NOTE: You can use neighbor shutdown command to disable a BGP neighbor or a peer group.
6 Add an enabled neighbor to the peer group.
CONFIG-ROUTER-BGP mode
neighbor {ip-address | ipv6-address | peer-group-name} peer-group peer-group-name
7 Add a neighbor as a remote AS.
CONFIG-ROUTER-BGP mode
neighbor {ip-address | ipv6-address | peer-group-name} remote-as as-number
• peer-group Name: 16 characters.
• as-number: the range is from 0 to 65535 (2-Byte) or 1 to 4294967295 | 0.1 to 65535.65535 (4-Byte) or 0.1 to 65535.65535
(Dotted format)
To add an external BGP (EBGP) neighbor, congure the as-number parameter with a number dierent from the BGP as-number
congured in the router bgp as-number command.
To add an internal BGP (IBGP) neighbor, congure the as-number parameter with the same BGP as-number congured in the
router bgp as-number command.
Examples of Viewing and Conguring Peer Groups
After you create a peer group, you can use any of the commands beginning with the keyword neighbor to congure that peer group.
When you add a peer to a peer group, it inherits all the peer group’s congured parameters.
A neighbor cannot become part of a peer group if it has any of the following commands congured:
• neighbor advertisement-interval
• neighbor distribute-list out
• neighbor filter-list out
• neighbor next-hop-self
• neighbor route-map out
• neighbor route-reflector-client
• neighbor send-community
A neighbor may keep its conguration after it was added to a peer group if the neighbor’s conguration is more specic than the peer
group’s and if the neighbor’s conguration does not aect outgoing updates.
NOTE
: When you congure a new set of BGP policies for a peer group, always reset the peer group by entering the clear ip
bgp peer-group peer-group-name command in EXEC Privilege mode.
To view the conguration, use the show config command in CONFIGURATION ROUTER BGP mode.
Border Gateway Protocol (BGP)
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