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Changing BGP Timers
To configure BGP timers, use either or both of the following commands.
Timer values configured with the neighbor timers command override the timer values configured with the timers bgp
command.
When two neighbors, configured with different 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 configured keepalive value is the new
keepalive value.
● Configure 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.
● Configure 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 configure BGP idle hold time, use the following commands.
Timer values configured with the neighbor timers extended command override the timer values configured with the
timers bgp extended command.
NOTE: The extended timer configuration is supported in Full-Switch mode only.
The peer remains in idle state based on the configured idle-holdtime. The less the idle-holdtime, lesser the peer
remains in idle state.
NOTE:
For the new idle-holdtime to take effect, you need to shutdown the respective peer manually using neighbor
shutdown command and enable the peer again.
● Configure 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.
● Configure idle-holdtime values for all BGP neighbors.
CONFIG-ROUTER-BGP mode
timers bgp 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)