ACI upgrade from 3.2 to 4.2 - No firmware/maintenance groups?

[vv0bbLeS]

Hello all,

We are preparing to upgrade our fabric from 3.2 to 4.2. In reading the official Cisco guide, in the section Important Notes on Upgrading the Cisco APIC and the Switch Software , I saw this bullet point (emphasis added) :

• Beginning with Release 4.0, node upgrade group policies are used instead of the firmware groups and maintenance groups that were used in previous releases. When upgrading Cisco APICs from a pre-4.0 release to Release 4.0(1) or later, you must remove all firmware group and maintenance group policies prior to the upgrade.

By removing the firmware and maintenance groups before the fabric upgrade, does that mean that I have to upgrade all the ACI leaves at once, i.e. I can't upgrade half of the leaves, and then once that's complete do the other half (e.g. the "odds and evens" approach) ? It sounds like the leaves will all just be lumped together and upgraded with no control over "when" any particular leaf goes down for an upgrade? Ideally I would still like to control which leaves get upgraded at a time, to minimize downtime to systems in the datacenter.

[vv0bbLeS · Accepted solution]

Nevermind, just found another forum post with the answer! The removal of the firmware/maintenance groups is just for the APIC upgrade. Once the APIC's are upgraded, you can create your maintenance groups again and then proceed with the switch upgrades like normal. Thanks!

Excerpt from linked forum post:

2. Remove all switch upgrade groups prior to upgrading APICs to 4.0 or later

Prior to APIC release 4.0, there are two switch upgrade groups, firmware group and maintenance group. Starting from APIC release 4.0, these groups are merged to simplify the user configuration. Once APICs are upgraded to 4.0 or later, users need to configure only maintenance groups for switch upgrades. In a later release, this group may be referred to as simply an upgrade group or an update group.

To avoid any unexpected behaviors, it is recommended to remove all switch firmware groups and maintenance groups prior to upgrading APICs to 4.0 or later from 3.x or older. Once the APICs are upgraded to 4.0 or later, create new switch upgrade groups and proceed with the switch upgrades. Even though the groups are for switches, the object model change happens on APICs. That's why this precautious operation needs to be performed before the APIC upgrades. Once APICs are upgraded to 4.0 or later, there is no need to perform this operation ever again when you upgrade APICs further.