Cisco IE 4000, Software Configuration Manual

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Configuring IP Unicast Routing
Configuring BGP
BEFORE YOU BEGIN
Enable BGP routing as described in the Enabling BGP Routing, page 850 .
DETAILED STEPS
To delete an aggregate entry, use the no aggregate-address address mask router configuration command. To return
options to the default values, use the command with keywords.
EXAMPLE
In the following example, an aggregate BGP address is created in router configuration mode. The path advertised for this
route will be an AS_SET consisting of all elements contained in all paths that are being summarized.
Switch(config)# router bgp 50000
Switch(config-router)# aggregate-address 10.0.0.0 255.0.0.0 as-set
In the following example, a route map called MAP-ONE is created to match on an AS-path access list. The path
advertised for this route will be an AS_SET consisting of elements contained in paths that are matched in the route map.
Switch(config)# ip as-path access-list 1 deny ^1234_
Switch(config)# ip as-path access-list 1 permit .*
Switch(config)# !
Switch(config)# route-map MAP-ONE
Switch(config-route-map)# match ip as-path 1
Switch(config-route-map)# exit
Switch(config)# router bgp 50000
Switch(config-router)# address-family ipv4
Command Purpose
1. configure terminal Enter global configuration mode.
2. router bgp autonomous-system Enter BGP router configuration mode.
3. aggregate-address address mask Create an aggregate entry in the BGP routing table. The
aggregate route is advertised as coming from the AS, and
the atomic aggregate attribute is set to indicate that
information might be missing.
4. aggregate-address address mask
as-set
(Optional) Generate AS set path information. This
command creates an aggregate entry following the same
rules as the previous command, but the advertised path will
be an AS_SET consisting of all elements contained in all
paths. Do not use this keyword when aggregating many
paths because this route must be continually withdrawn
and updated.
5. aggregate-address address-mask
summary-only
(Optional) Advertise summary addresses only.
6. aggregate-address address mask
suppress-map map-name
(Optional) Suppress selected, more specific routes.
7. aggregate-address address mask
advertise-map map-name
(Optional) Generate an aggregate based on conditions
specified by the route map.
8. aggregate-address address mask
attribute-map map-name
(Optional) Generate an aggregate with attributes specified
in the route map.
9. end Return to privileged EXEC mode.
10. show ip bgp neighbors
[ advertised-routes ]
Verify the configuration.
11. copy running-config startup-config (Optional) Save your entries in the configuration file.