12-07-2023 06:08 PM
Hi, while studying configuration of VRRP and HSRP, I noticed that there is a difference in configuration on the router in STANDBY state.
Obviously, it's the same FHRP and as far as I know, the equipment with configuration works with priority preemption in the same way, except for the difference between VRRP and HSRP, but I wonder why you put PLMMPT settings separately for the router with low priority (STAND BY) of HSRP, but VRRP didn't put a separate PREMPT command. I would appreciate it if you could explain it and if there is any internal Cisco material that I can read.
Below is the actual picture of the equipment that I referred to.
Please refer to it when explaining.
VRRP
HSRP
12-07-2023 06:39 PM
Hello,
Its because as soon as the Primary device fails the backup device will "preempt" immediately. If you want to configure a delay in there just to make sure the Primary did in fact go down and its not due to a little bit of traffic latency then you can configure it to do so.
I'm guessing the reason its not configured on the Primary is because when the Primary comes back online it should take back over the role immediately.
I believe you can also configure the device to not take over as Primary and to wait so many seconds after bootup before electing itself. It just some settings to help control as many aspects of you network and get more granular with configurations.
-David
12-07-2023 09:54 PM - edited 12-07-2023 09:54 PM
Preempt is default in vrrp
Optional in hsrp
That why you see it in hsrp config and it missing from vrrp.
MHM
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide