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Changing BGP keepalive and hold timers
BGP uses timers to control the activity of sending the keepalive messages to its neighbors or peers. Also, you can adjust the
interval of how long the device has to wait for a keepalive messge from a neighbor before declaring the peer dead. To configure
BGP timers, use either or both of the following commands.
To change the BGP timers for all neighbors, use timers bgp command. To change the BGP keepalive and holdtime timers for
a specific neighbor or peer, use the neighbor timers command.
NOTE: 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 | ipv6-address | peer-group-name} timers keepalive holdtime
○ keepalive: Time interval, in seconds, between keepalive messages sent to the neighbor routers. The range is from 1 to
65535. The default is 60 seconds.
○ holdtime: Time interval, in seconds, between the last keepalive message and declaring the BGP peer is dead. The range
is from 3 to 65536. The default is 180 seconds.
● Configure timer values for all neighbors.
CONFIG-ROUTER-BGP mode
timers bgp keepalive holdtime
○ keepalive: Time interval, in seconds, between keepalive messages sent to the neighbor routers. The range is from 1 to
65535. The default is 60 seconds.
○ holdtime: Time interval, in seconds, between the last keepalive message and declaring the BGP peer is dead. The range
is from 3 to 65536. The default is 180 seconds.
DellEMC# configure terminal
DellEMC(conf)# router bgp 400
DellEMC(conf-router_bgp)# network 10.1.1.0 mask 255.255.255.0
DellEMC(conf-router_bgp)# timers bgp 80 120
DellEMC(conf-router_bgp)# exit
In the above example configuration, the BGP timers are set with keepalive time as 80 seconds with which the system sends
keepalive messages to the BGP peer and holdtime as 120 seconds with which the system waits for a message from the BGP
peer before concluding that the peer is dead.
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.
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
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Border Gateway Protocol (BGP)