Concept Guide

Changing BGP Timers
To congure BGP timers, use either or both of the following commands.
Timer values congured with the neighbor timers command override the timer values congured with the timers bgp command.
When two neighbors, congured with dierent keepalive and holdtime values, negotiate for new values, the resulting values are as
follows:
• the lower of the holdtime values is the new holdtime value, and
• whichever is the lower value; one-third of the new holdtime value, or the congured keepalive value is the new keepalive
value.
• Congure timer values for a BGP neighbor or peer group.
CONFIG-ROUTER-BGP mode
neighbors {ip-address | peer-group-name} timers keepalive holdtime
– keepalive: the range is from 1 to 65535. Time interval, in seconds, between keepalive messages sent to the neighbor routers.
The default is 60 seconds.
– holdtime: the range is from 3 to 65536. Time interval, in seconds, between the last keepalive message and declaring the router
dead. The default is 180 seconds.
• Congure timer values for all neighbors.
CONFIG-ROUTER-BGP mode
timers bgp keepalive holdtime
– keepalive: the range is from 1 to 65535. Time interval, in seconds, between keepalive messages sent to the neighbor routers.
The default is 60 seconds.
– holdtime: the range is from 3 to 65536. Time interval, in seconds, between the last keepalive message and declaring the router
dead. The default is
180 seconds.
To view non-default values, use the show config command in CONFIGURATION ROUTER BGP mode or the show running-
config bgp command in EXEC Privilege mode.
Setting the extended timer
To congure BGP idle hold time, use the following commands.
Timer values congured with the neighbor timers extended command override the timer values congured with the timers bgp
extended command.
NOTE
: The extended timer conguration is supported in Full-Switch mode only.
The peer remains in idle state based on the congured idle-holdtime. The less the idle-holdtime, lesser the peer remains in idle
state.
NOTE
: For the new idle-holdtime to take eect, you need to shutdown the respective peer manually using neighbor
shutdown command and enable the peer again.
• Congure idle-holdtime values for a BGP neighbor or peer group.
CONFIG-ROUTER-BGP mode
neighbors {ip-address | ipv6-address | peer-group-name} timers extended idle-holdtime
idle-holdtime: the range is from 1 to 32767. Time interval, in seconds, during which the peer remains in idle state. The default is 15
seconds.
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Border Gateway Protocol IPv4 (BGPv4)