Standby VSS sup replaced, need configuration help

[mo shea]

Hi...

We had a power outage in our Data Center. After power was restored, the originally active VSS 6509 was powered, then the standby vss 6509 was powered on. The VSS state was briefly up, but then the standby 6509 rebooted several times before going to rommon. We contacted TAC and it seems that the problem is hardware related, so we will be receiving another Supervisor engine shortly, to be fixed in the standby 6509.

My question is when configuring the standby 6509, shall I clear the vss config on the active 6509 and start vss all over or perform the configuration steps on the standby vss only.

One more thing is that the vss pair are running a modular IOS (dont have the version right now), could this bee another reason for the standby failure? Shall I go for a non modular IOS (perhaps SXI5) to beon the safe side for future?

All help is appreciated

Thanks.

[Reza Sharifi]

Hi,

My question is when configuring the standby 6509, shall I clear the vss  config on the active 6509 and start vss all over or perform the  configuration steps on the standby vss only.

No, you don't need to clear the config.  You only need to clear the config on the new sup (stand-by) before attaching it to the VSS pair.

One more thing is that the vss pair are running a modular IOS (dont have  the version right now), could this bee another reason for the standby  failure? Shall I go for a non modular IOS (perhaps SXI5) to beon the  safe side for future?

It is deifinatky a good idea to use non-modular as all the new 6500 images are non-modular.  Cisco is going away from modular IOS for the 6500 series.  Remember one thing, when upgrading from a modular to a non-modular IOS you can not use ISSU.  You have to copy the image in both devices and reboot them. Since you are getting a new sup, it may be a good idea to upgrade the IOS now during an outage window.

HTH

[mo shea]

Thank you for the reply.

I want to know how to make sure the standby 6509 I am configuring now will assume standby status, and not try to become active?

Thanks

[Reza Sharifi · Accepted solution]

As long as your primary is running, when you bring the stand-by on line, it will be the stand-by.  In the case you are upgrading your IOS by rebooting both switches, if you turn on the primary device a few second before the stand-by you will also see that the stand-by boots after the primary and become the stand-by switch.

HTH

[mo shea]

Thanks for the reply,

I would like to clarify some more points before proceeding with the upgrade,

- How to confirm that the command 'switch accept mode virtual' has been entered. While researching I found that it is recommended by the vss deployment best practices,

http://www.cisco.com/en/US/products/ps9336/products_tech_note09186a0080a7c837.shtml

and I really do not remember if we had configured it on the original VSS system, although vss was successfully established and worked for 2 years before last week's power outage

- Currently the Actvie Vss 6509 has the vlan port assignments of the faulty standby 6509. Will the same config get transferred to this faulty 6509 once repaired and VSS established?

- Since now we are planning to upgrade the ios as well as re-establish vss, which path will lead to least number of switch reboots, least downtime,

- PATH 1 - load the similar ios (sxh5), currently running on the Active 6509, on to the repaired 6509 and establish VSS then after network stability, upgrade the Active and standby 6509s to ios SXI5 and reboot them together (with a few seconds between the active and standby)

- PATH 2 - load the new ios SXI5 on to the ACTVIE 6509, reboot, then upgrade the ios on the repaired 6509, reboot then establish VSS

All Help is appreciated

Regards 

[venkata dandu]

Hi

    We recently had the same problem. What i did was

• i loaded the repaired VSS Pair's SUP(Standby 6500) with the IOS running on the active switch.
  
• Configured the VSS basic config, reloaded the standby switch and connected the VSL Links.
  
• Once the Standby VSS switch is up it will comeup in RRP mode as the running config is matched between the pairs.
  
• You do a copy running-config start-config on the active VSS switch which will do a copy to the standby VSS switch aswell.
  
• No you reboot the standby switch and everything will work as it was before.
  

  HTH

[mo shea]

Thanks Venkata for your feedback,

Your approach seems to go along path one I mentioned before. So you connected the physical VSL links during the first reload or after, because if you've done the latter won't the switch become Active.

Did you use the 'switch accept mode virtual' command ?

Thanks again

[venkata dandu]

Hi;

    I connected the physical links during the first reload. Yes if you connect them after then it will become active. Yes i did use 'switch accept mode virtual' after the first reload. i had the console access to the standby switch as the switch is still stuck in RPR mode as the config mismatch between the pairs. After the ' wr mem' on the primary switch it is copied over to the standby.

HTH

[mo shea]

Thanks again for the info.

Our downtime is scheduled for Wedneday afternoon, hope it would be a short one. Any idea which IOS is recommended and stable for VSS deployments.

Regards.

[venkata dandu]

12.2(33) SXJ1 is latest one which passed the 'safe harbor test' by cisco and it also supports latest cards like WiSM2 etc. We arleady tested this IOS and we are about to have ours upgraded to these.