timers value on backup routers in vrrp

Answered Question
Jan 23rd, 2009
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Hi every body!

I don't find command to configure the timers value on back up routers in vrrp .

Is there any command for that?


thanks a lot!


Correct Answer by Mark Yeates about 8 years 4 months ago

I wasn't totally sure what you were looking for. What I think you are looking for is the "delay" command under VRRP. This is the for the number of seconds that the router will delay before issuing an advertisement claiming master ownership.


vrrp group preempt [delay seconds]


http://www.cisco.com/en/US/docs/ios/12_0st/12_0st18/feature/guide/st_vrrpx.html#wp1025904


HTH,

Mark

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sarahr202 Fri, 01/23/2009 - 17:17
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Thanks a lot mark!

The command " vrrp 1 timers advertise" only tells the router that if you are master, use the interval specified for the advertisements.


The command " vrrp 1 timers learn " tell the router that if you are backup router, please learn the timer value from the master.


The question is if there is any way we can configure the hold time value on backup router?


thanks a lot!

Correct Answer
Mark Yeates Fri, 01/23/2009 - 18:01
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I wasn't totally sure what you were looking for. What I think you are looking for is the "delay" command under VRRP. This is the for the number of seconds that the router will delay before issuing an advertisement claiming master ownership.


vrrp group preempt [delay seconds]


http://www.cisco.com/en/US/docs/ios/12_0st/12_0st18/feature/guide/st_vrrpx.html#wp1025904


HTH,

Mark

sarahr202 Fri, 01/23/2009 - 19:40
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Hi Mark !

Thanks for your reply. On the second thought over my dinner (:-), I came with following reason.

I quoted you here:


"This is the for the number of seconds that the router will delay before issuing an advertisement claiming master ownership"

I believe " vrrp group preempt[delay seconds]"

only tells router that please don't become master for the time specified .

The hold time on other hand tell the router :

1) if you don't hear from master for the time specified in hold timer, consider the master dead and start advertising yourself as master.

The point to be noted here is advertising being a master and be a master are different things.

The command " vrrp group preempt delay[seconds]" does not tell backup router when to start advertising as a master, rather it tells the backup router to wait by specified amount of time in the command before becoming the master.

Let say r1,r2 , r3 are in vrrp group, all are using the default priority of 100.

r1 has 10.10.10.10,r2 has 9.9.9.9 and r3 has 8.8.8.8. Since priority is 100 on all routers, ip address will be used to select master.

r1 is elected as master

Further assume we configure " vrrp 1 preempt delay 15 seconds on r2.

Now r1 goes down, r2 and r3 will wait for hold time then start sending their own vrrp advertisements claiming to be the master.Based on the vrrp advertisement received from r3,

r2 realize that it should be the master but the command" vrrp 1 preempt delay 15" tells the r2 you got to wait for 15 seconds before becoming the master.


I welcome any correction from anyone.


Thanks a lot Mark!


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