Concept Guide

NOTE: 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 | 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.
• Congure 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.
Example conguration of BGP keepalive and hold timers
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 conguration, 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 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.
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
Border Gateway Protocol (BGP)
231