Nexus 6k ISSU & Upgrading Best Practise L3

Hello,

I’ve been researching into upgrading 2 Nexus 6k switches which are used as a layer 3 core and have 2000 series FEX’s attached.

I’m hoping to confirm behaviour of upgrading Nexus switches after reading Cisco documentation on it.

1. First, they are being used for L3 features/routing etc. It appears ISSU not supported for L3 at all and will therefore be disruptive. My understanding is without removing all L3 features and L3 license it will be impacting. So we could do this with one switch at a time but doesn’t seem particularly feasible and we may just have to take the hit with the upgrade impact anyway as removing L3 features could have it’s own impact if not done correctly with routing convergence etc.

2. If we wanted to do a basic upgrade like on a catalyst typical switch I believe we would get the images on check the image compatibility and do a ‘install all’ on both the primary and secondary switch in VPC topology. (follow the good documentation Cisco have generally on upgrade procedure checks https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus6000/sw/upgrade/731\_N1\_1/n6000\_upgrade\_downgrade\_731\_n1\_1.html#64244)

Any tips or suggestions would be welcomed on the L3 part as not getting my head round what is best practise and it should be clear to some that this is not something I have done before.

Thanks