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New Member

SSO switchover

Hi all,

Currently I am having an issue with 12406.

One of my primary 4 slot RE has failed over to 5 slot RE hot standby. Less 24 hours the 5 slot has switch over back to 4 again. Keep going like that within 3 days twice per day.

My question is when first attempt from 4 to 5, why 5 need to switch back 4 by itself? Is possible certain time frame, slot 5 detect or sense that 4 is stable, it will auto switch over? It doesnt make any sense to me because why switch over since slot 5 is running fine. If switch over 0-3s interrupt services.

I also support Juniper. It will switch over until i perform manual switch by command prompt.

Any ref for SSO behavior? I tried to luck

Cisco Employee

Re: SSO switchover

Hi lawwm,

That is not normal behaviour. If the failed RP manages to reboot ok then it becomes the new standby and stays that way until either:

• A fault condition that causes the active RP to crash or reboot-automatic switchover

• The active RP is declared dead (not responding)-automatic switchover

• The CLI is invoked-manual switchover

Check the log. Also checkout "show redundancy" and it's various options.

Check that both RPs are running the same version of IOS.

Here's some further information:')">

New Member

Re: SSO switchover


Thanks for your information and clarification.