Reference Guide

When you disable a peer group, all the peers within the peer group that are in the ESTABLISHED state move to the IDLE
state.
To view the status of peer groups, use the show ip bgp peer-group command in EXEC Privilege mode, as shown
in the following example.
Example of the show ip bgp peer-group Command
FTOS>show ip bgp peer-group
Peer-group zanzibar, remote AS 65535
BGP version 4
Minimum time between advertisement runs is 5 seconds
For address family: IPv4 Unicast
BGP neighbor is zanzibar, peer-group internal,
Number of peers in this group 26
Peer-group members (* - outbound optimized):
10.68.160.1
10.68.161.1
10.68.162.1
10.68.163.1
10.68.164.1
10.68.165.1
10.68.166.1
10.68.167.1
10.68.168.1
10.68.169.1
10.68.170.1
10.68.171.1
10.68.172.1
10.68.173.1
10.68.174.1
10.68.175.1
10.68.176.1
10.68.177.1
10.68.178.1
10.68.179.1
10.68.180.1
10.68.181.1
10.68.182.1
10.68.183.1
10.68.184.1
10.68.185.1
FTOS>
Configuring BGP Fast Fail-Over
By default, a BGP session is governed by the hold time.
BGP routers typically carry large routing tables, so frequent session resets are not desirable. The BGP fast fail-over
feature reduces the convergence time while maintaining stability. The connection to a BGP peer is immediately reset if a
link to a directly connected external peer fails.
When you enable fail-over, BGP tracks IP reachability to the peer remote address and the peer local address. Whenever
either address becomes unreachable (for example, no active route exists in the routing table for peer IPv6 destinations/
local address), BGP brings down the session with the peer.
The BGP fast fail-over feature is configured on a per-neighbor or peer-group basis and is disabled by default.
To enable the BGP fast fail-over feature, use the following command.
To disable fast fail-over, use the [no] neighbor [neighbor | peer-group] fail-over command in
CONFIGURATION ROUTER BGP mode.
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