Configuration Guide User guide

1364 FastIron Configuration Guide
53-1002494-02
Basic configuration tasks required for BGP4
Applying a peer group to a neighbor
After you configure a peer group, you can add neighbors to the group. When you add a neighbor to
a peer group, you are applying all the neighbor attributes specified in the peer group to the
neighbor.
To add neighbors to a peer group, enter commands such as the following.
Brocade(config-bgp-router)#neighbor 192.168.1.12 peer-group PeerGroup1
Brocade(config-bgp-router)#neighbor 192.168.2.45 peer-group PeerGroup1
Brocade(config-bgp-router)#neighbor 192.168.3.69 peer-group PeerGroup1
The commands in this example add three neighbors to the peer group “PeerGroup1”. As members
of the peer group, the neighbors automatically receive the neighbor parameter values configured
for the peer group. You also can override the parameters (except parameters that govern outbound
traffic) on an individual neighbor basis. For neighbor parameters not specified for the peer group,
the neighbors use the default values.
Syntax: neighbor <ip-addr> peer-group <peer-group-name>
The <ip-addr> parameter specifies the IP address of the neighbor.
The <peer-group-name> parameter specifies the peer group name.
NOTE
You must add the peer group before you can add neighbors to it.
Administratively shutting down a session with a BGP4 neighbor
You can prevent the Layer 3 switch from starting a BGP4 session with a neighbor by
administratively shutting down the neighbor. This option is very useful for situations in which you
want to configure parameters for a neighbor but are not ready to use the neighbor. You can shut
the neighbor down as soon as you have added it the Layer 3 switch, configure the neighbor
parameters, then allow the Layer 3 switch to re-establish a session with the neighbor by removing
the shutdown option from the neighbor.
When you apply the new option to shut down a neighbor, the option takes place immediately and
remains in effect until you remove the option. If you save the configuration to the startup-config file,
the shutdown option remains in effect even after a software reload.
NOTE
The software also contains an option to end the session with a BGP4 neighbor and thus clear the
routes learned from the neighbor. Unlike this clear option, the option for shutting down the neighbor
can be saved in the startup-config file and thus can prevent the Layer 3 switch from establishing a
BGP4 session with the neighbor even after reloading the software.
NOTE
If you notice that a particular BGP4 neighbor never establishes a session with the Brocade Layer 3
switch, check the Layer 3 switch running-config and startup-config files to see whether the
configuration contains a command that is shutting down the neighbor. The neighbor may have been
shut down previously by an administrator.