VSS Quad SUP - how to switch From Active To the CSSO SUP on te primary Switch

[zizou6500]

Hi Community,

I'll need your help to advise on the above, from my reading there is no way to switch the standby SUP on the primary Switch. Resetting/reloading the active SUP will automatically failover to the Active SUP in the second switch which will take the primary role.

[balaji.bandi]

if you want to standby to move active - means you need to switch over from active to standby right ? - is this what you looking

To force a switchover from the VSS active to the VSS standby supervisor engine, use the redundancy force-switchover command.

[zizou6500]

Hi Balaji,

Thank you for your reply.

Indeed, I do not want to switchover from the VSS active to the VSS standby. I want just to switch from the Active SUP to the standby SUP on the Active VSS.

[Reza Sharifi]

Hi,

There is no way to fail from primary sup to backup sup in the same chassis. When you fail it, it will fail to the backup chassis. That is actually one of the reasons that quad sup VSS is not popular.

HTH 

[balaji.bandi]

@Reza Sharifi  i agree - may be i have not cleared in the old post - Quad supervisor work in Z fail over method.

[Reza Sharifi]

BB,

Yeah, In my opinion, quad sup deployments are a waste of money and make failover and redundancy complicated!

Reza

[balaji.bandi]

Agreed, but some organisation want to very high availability and cisco smart support 4 hours replacement  also (not make any sense for me). may be business requiement and complaince.

[zizou6500]

Thank you for your feedback. Indeed I'm expecting an issue with the active SUP. Which will be the best way to reset this card, please? Here are the commands as far as I know: #hw-module switch 1 module x reset #redundancy force-switchover I think both of them will result in the reboot of the VSS Active, but I want just to know which way would be better.

[Reza Sharifi]

You want to use 

redundancy force-switchover

so you fail to the backup chassis.

HTH

[zizou6500]

Hi Reza, Thank you for your feedback.

So the command "redundancy force-switchover" has the same behavior as the command "hw-module switch 1 module x reset", please (rebooting the primary chassis)? Is it better to use the first command?

[Reza Sharifi]

Hi,

Yes, since this is VSS, I would do redundancy force-switchover

Please make sure you do this in a maintenance window just in case something goes wrong. Also, before you do this, make sure all your access switches are connected to both chassis.

HTH

[zizou6500]

Hi Reza,

Thank you for your support.

Last question: when issuing the command "redundancy force-switchover", the SW1 (primary chassis) will it reboot (including the line cards..etc), please?

[balaji.bandi]

yes correct - to make standby chansis active

that is the reason always suggest to you should have dual path, orphan ports have downtime.

[zizou6500]

Thank you for your feedback. Indeed I'm expecting an issue with the active SUP. Which will be the best way to reset this card, please? Here are the commands as far as I know:  "hw-module switch 1 module x reset"  & "redundancy force-switchover" I think both of them will result in the reboot of the VSS Active, but I want just to know which way would be better.

[paul driver]

Hello

As the guys have mentioned:
If the primary sup fails in chassis X the standby sup in Chassis Y becomes active as such the standby sup in chassis X sup becomes standby.

Next if the primary sup fails in chassis Y the 2nd standby sup in Chassis X becomes active and the 2nd standby sup in chassis Y sup becomes standby.