38-61
Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide
OL-12247-04
Chapter 38 Configuring IP Unicast Routing
Configuring BGP
Configuring BGP Neighbors and Peer Groups
Often many BGP neighbors are configured with the same update policies (that is, the same outbound
route maps, distribute lists, filter lists, update source, and so on). You can group neighbors with the same
update policies into peer groups to simplify configuration and to make updating more efficient. When
you have configured many peers, we recommend this approach.
To configure a BGP peer group, you create the peer group, assign options to the peer group, and add
neighbors as peer group members. You configure the peer group by using the
neighbor
router
configuration commands. By default, peer group members inherit all the configuration options of the
peer group, including the remote-as (if configured), version, update-source, out-route-map,
out-filter-list, out-dist-list, minimum-advertisement-interval, and next-hop-self. All peer group members
also inherit changes made to the peer group. You can also configure members to override the options that
do not affect outbound updates.
To assign configuration options to an individual neighbor, specify any of these router configuration
commands by using the neighbor IP address. To assign the options to a peer group, specify any of the
commands by using the peer-group name. You can disable a BGP peer or peer group without removing
all the configuration information by using the
neighbor shutdown
router configuration command.
Beginning in privileged EXEC mode, use these commands to configure BGP peers:
Step 9
show ip bgp community
Verify the configuration.
Step 10
copy running-config startup-config
(Optional) Save your entries in the configuration file.
Command
Purpose
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
router bgp
autonomous-system
Enter BGP router configuration mode.
Step 3
neighbor
peer-group-name
peer-group
Create a BGP peer group.
Step 4
neighbor
ip-address
peer-group
peer-group-name
Make a BGP neighbor a member of the peer group.
Step 5
neighbor
{
ip-address
|
peer-group-name
}
remote-as
number
Specify a BGP neighbor. If a peer group does not have a
remote-as
number
, use this command to create peer groups
containing EBGP neighbors. The range is 1 to 65535.
Step 6
neighbor
{
ip-address
|
peer-group-name
}
description
text
(Optional) Associate a description with a neighbor.
Step 7
neighbor
{
ip-address
|
peer-group-name
}
default-originate
[
route-map
map-name
]
(Optional) Allow a BGP speaker (the local router) to send the
default route 0.0.0.0 to a neighbor for use as a default route.
Step 8
neighbor
{
ip-address
|
peer-group-name
}
send-community
(Optional) Specify that the COMMUNITIES attribute is sent to
the neighbor at this IP address.
Step 9
neighbor
{
ip-address
|
peer-group-name
}
update-source
interface
(Optional) Allow internal BGP sessions to use any operational
interface for TCP connections.
Step 10
neighbor
{
ip-address
|
peer-group-name
}
ebgp-multihop
(Optional) Allow BGP sessions, even when the neighbor is not
on a directly connected segment. The multihop session is not
established if the only route to the multihop-peer address is the
default route (0.0.0.0).
