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After you create a peer group, you can configure route policies for it. For information about configuring route policies for a peer
group, refer to Filtering BGP Routes. See Example-Configuring BGP peer groups for configuring multiple BGP neighbors and
enabling peer groups.
Configuring Peer Groups
To configure a peer group, use the following commands.
1. Enter the router configuration mode and the AS number.
CONFIG mode
router bgp as-number
2. Create a peer group by assigning a name to it.
CONFIG-ROUTER-BGP mode
neighbor peer-group-name peer-group
3. Enable the peer group.
CONFIG-ROUTER-BGP mode
neighbor peer-group-name no shutdown
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, configure the as-number parameter with a number different from the BGP
as-number configured in the router bgp as-number command.
To add an internal BGP (IBGP) neighbor, configure the as-number parameter with the same BGP as-number configured in
the router bgp as-number command.
After you create a peer group, you can use any of the commands beginning with the keyword neighbor to configure that peer
group.
When you add a peer to a peer group, it inherits all the peer group’s configured parameters.
A neighbor cannot become part of a peer group if it has any of the following commands configured:
● 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
Border Gateway Protocol (BGP)
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