VRRP timers learn - best practice?

[vv0bbLeS]

Hello all,

Because VRRP timers have to match on all the switches in the group, is it a best practice to configure vrrp timers learn on all VRRP switches in the group? Conversely, is there a scenario where vrrp timers learn would NOT be a good idea?

[David Ruess · Accepted solution]

Hello,

If you have several VRRP routers such as your primary/secondary and other backups then it probably wouldn’t hurt to use the learn command so you only have to configure on one device.

However I’m a fan of configuring the timers manually just because the “learn” fails for any reason. That’s just my preference.

-David

[M02@rt37 · Accepted solution]

Hello @vv0bbLeS

In complement to David's answer, vrrp timer learn make troubleshooting harder, and in some design yes you don't want timers to adjust dynamically _ for example in highly controled HA environments where deterministic failover timing is required or when you want to guarantee convergence aligned with routing protocol timer.

[balaji.bandi · Accepted solution]

All routers in a VRRP group must use the same timer values. If the same timer values are not set, the routers in the VRRP group will not communicate with each other and any misconfigured router will change its state to master.

setting the correct timers to get optimal outcome to detect. 

[paul driver · Accepted solution]

Hello
TBH- I dont think Cisco has any best practice stated for VRRP
Now obviously, you don’t have to set any hello timer for VRRP to work, it will default to 1 second.
However If you wish to change this default, then yes you can set it just on the master device and have the members in the group to learn automatically or as you mentioned manually set each device to the correct value.

Personally, I manually set each device in any of our FHRP deployments as in most cases we also have authentication & track/decrement/delay values manually set

[vv0bbLeS]

Excellent, that all makes sense! Thank you all!

[M02@rt37]

You're so welcome @vv0bbLeS