ios upgrade using eFSU 6500 VSS

[mmcfarland727]

I need to upgrade the IOS on our 6500s, i want to do this by using the eFSU concept. Please can someone tell me if i am able to go from the current IOS to the new one.  Cisco haven't updated there SX/Y eFSU (ISSU Phase 1) Compatibility Matrix spreadsheet. I have spoke to our Cisco/maintenance support and they reckon you cant jump maintenance release numbers but according to the matrix's you can... Confused!?!

Current IOS: s2t54-ipservicesk9-mz.SPA.151-2.SY.bin

New IOS: s2t54-ipservicesk9-mz.SPA.151-2.SY3.bin

[Leo Laohoo]

I'm not a big fan of eFSU because it doesn't seem to work for me most of the time.  All my IOS upgrade with Sup720 is done the old method which has higher success rate.

[mmcfarland727]

Please can you elaborate on what doesn't work when you try using the eFSU?

[Leo Laohoo · Accepted solution]

FSU/eFSU is beneficial if you've got VSS and/or dual supervisor (per chassis).  

When FSU/eFSU works you should get minimal outage.  If it doesn't your supervisors will boot one after another.  This is the bit which I have witnessed in the past.  Don't want to go through that again, so I use a different method but this means that the VSS pairs go down.

[mmcfarland727]

Thank you for your reply,  we have a 6509 running VSS with a single supervisor in each chassis. From what you have said it should run smoothly with minimal outage if any.

[Leo Laohoo]

Thanks for taking the time to rate our posts.  

Ok, so you have a VSS pair with a single supervisor card.  Just like me and about 80% the rest of the VSS worldwide.  

Bear in mind that with any single-supervisor chassis, if the supervisor reboots, the chassis becomes a piece of brick.  

So when I say, minimal, you get one half of the pair operational while the other half goes down while the supervisor card reboots.  

[mmcfarland727]

I successfully upgraded last week with no downtime apart from each supervisor rebooting. As everything is dual-homed there was no lose of connectivity.

Thank you for responding to my posts

[rami_alaydi]

Hi,

Thanks for sharing this.

I am confused about the Cisco 6500 upgrade.

What is the difference between upgrading the VSS chassis and the IOS of the Core Switch?

Currently i have 15.1(1) SY for the Core Switch and i need to upgrade it to 15.1(2) SY. All i see the commands to upgrade it is through FSU or eFSU for IOS but what about the VSS chassis? is there any upgrade for it? How to do that in case there is? 

Will really appreciate your help in this matter.