Cisco IE 4000, Software Configuration Manual

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Configuring IP Unicast Routing
Configuring BGP
To disable an existing BGP neighbor or neighbor peer group, use the neighbor shutdown router configuration command.
To enable a previously existing neighbor or neighbor peer group that had been disabled, use the no neighbor shutdown
router configuration command.
EXAMPLE
The following example configures a peer group and sets the minimum time between sending BGP routing updates to 10
seconds for the peer group:
Switch(config)#
router bgp 45000
Switch(config-router)# neighbor mygroup peer-group
Switch(config-router)# neighbor 192.168.1.2 remote-as 40000
Switch(config-router)#
neighbor 192.168.3.2 remote-as 50000
Switch(config-router)# neighbor 192.168.1.2 peer-group mygroup
Switch(config-router)# neighbor 192.168.3.2 peer-group mygroup
Switch(config-router)#
neighbor mygroup advertisement-interval 10
Configuring Aggregate Addresses
Classless interdomain routing (CIDR) enables you to create aggregate routes (or supernets ) to minimize the size of
routing tables. You can configure aggregate routes in BGP either by redistributing an aggregate route into BGP or by
creating an aggregate entry in the BGP routing table. An aggregate address is added to the BGP table when there is at
least one more specific entry in the BGP table.
18. neighbor { ip-address | peer-group-name }
timers keepalive holdtime
(Optional) Set timers for the neighbor or peer group.

The keepalive interval is the time within which
keepalive messages are sent to peers. The range is
1 to 4294967295 seconds; the default is 60.

The holdtime is the interval after which a peer is
declared inactive after not receiving a keepalive
message from it. The range is 1 to 4294967295
seconds; the default is 180.
19. neighbor { ip-address | peer-group-name }
weight weight
(Optional) Specify a weight for all routes from a
neighbor.
20. neighbor { ip-address | peer-group-name }
distribute-list { access-list-number |
name } { in | out }
(Optional) Filter BGP routing updates to or from
neighbors, as specified in an access list.
21. neighbor { ip-address | peer-group-name }
filter-list access-list-number { in | out |
weight weight }
(Optional) Establish a BGP filter.
22. neighbor { ip-address | peer-group-name }
version value
(Optional) Specify the BGP version to use when
communicating with a neighbor.
23. neighbor { ip-address | peer-group-name }
soft-reconfiguration inbound
(Optional) Configure the software to start storing
received updates.
24. end Return to privileged EXEC mode.
25. show ip bgp neighbors Verify the configuration.
26. copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose