HSRP States and Timers
As we know by now, a router can act as both the active HSRP router (forwarding), and/or it can also be a passive standby HSRP router which is ready to take over the active role if the presently active router fails.
From the moment a router is configured with HSRP, the router will start to send and receive HSRP HELLO messages to begin determining which state it will assume in the group.
| Initial |
| This state is entered when an interface first becomes available or sometimes through configuration amendments |
| Listen |
| The router has not determined the virtual IP address yet and has not seen a hello message from the active router. In this state, the router waits to hear from the active router |
| Learn |
| The router now knows the virtual IP address, but the router is neither set to be the active router nor the standby router. It will listen for hello messages from those routers |
| Speak |
| The router sends periodic hello messages every 3 seconds and actively participates in the election of the active and/or standby router. |
| Standby |
| The router is a candidate to become the next active router and sends periodic hello messages. |
By default, the active and standby HSRP routers send hello messages to the HSRP group multicast address every 3 seconds.
If the standby router does not receive a hello message from the active router after 10 seconds, it will then become active.
If you wish to speed up the process, you can tamper with the timer settings of failover or preemption.
Changing the hello and hold timers
R1(config)# interface [interface id] R1(config-if)# standby [group] timers [hello-timer-seconds] [hold-timer-seconds]
Changing the hello and holder timers Complete Configuration Example
R1> enable R1# configure terminal R1(config)# interface interface g0/1 R1(config-if)# standby 1 timers 1 2 R1(config-if)# exit R1(config)# exit R1#
[NOTE] If you tamper with these settings, it is recommended not to set the hello timer below 1 second or the hold timer below 4 seconds