user manual

42-63
Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-21521-01
Chapter 42 Configuring IP Unicast Routing
Configuring BGP
Beginning in privileged EXEC mode, use these commands to configure BGP route dampening:
To disable flap dampening, use the no bgp dampeni
ng router configuration command without
keywords. To set dampening factors back to the default values, use the no bgp dampening router
configuration command with values.
Monitoring and Maintaining BGP
You can remove all contents of a particular cache, table, or database. This might be necessary when the
contents of the particular structure have become or are suspected to be invalid.
You can display specific statistics, such as the conte
nts of BGP routing tables, caches, and databases.
You can use the information to get resource utilization and solve network problems. You can also display
information about node reachability and discover the routing path your device’s packets are taking
through the network.
Table 42-8 li
sts the privileged EXEC commands for clearing and displaying BGP. For explanations of
the display fields, see the Cisco IO
S IP Command Reference, Volume 2 of 3: Routing Protocols,
Release 12.2.
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
router bgp autonomous-system Enter BGP router configuration mode.
Step 3
bgp dampening Enable BGP route dampening.
Step 4
bgp dampening half-life reuse suppress
max-suppress [route-map map]
(Optional) Change the default values of route dampening
factors.
Step 5
end Return to privileged EXEC mode.
Step 6
show ip bgp flap-statistics [{regexp regexp} |
{filter-list list} | {address mask [longer-prefix]}]
(Optional) Monitor the flaps of all paths that are flapping. The
statistics are deleted when the route is not suppressed and is
stable.
Step 7
show ip bgp dampened-paths (Optional) Display the dampened routes, including the time
remaining before they are suppressed.
Step 8
clear ip bgp flap-statistics [{regexp regexp} |
{filter-list list} | {address mask [longer-prefix]}
(Optional) Clear BGP flap statistics to make it less likely that a
route will be dampened.
Step 9
clear ip bgp dampening (Optional) Clear route dampening information, and unsuppress
the suppressed routes.
Step 10
copy running-config startup-config (Optional) Save your entries in the configuration file.
Ta ble 42-11 IP BGP Clear and Show Commands
Command Purpose
clear ip bgp add
ress Reset a particular BGP connection.
clear ip bgp * Reset all BGP connections.
clear ip bgp peer-group ta
g Remove all members of a BGP peer group.