We recently upgraded a few of our UCS domains from 3.1(1h) and 3.1(2b) up to 3.2(1d) and we had issues with a few IO modules hanging for up to 2 hours with trying to activate the firmware.
The backup version was updated with no issues, but then the activation stalled through anywhere from 16 to 30 tries before failing.
We decided to leave most of the faulted IOMs alone to see what they would do, but after 2 hours we decided to attempt a reset of one IO module, and that just made it angry…
We took another IOM and ran a peer rest instead, and that kicked things into gear. Once the module had been reset, it went directly into auto-upgrade and was updated within the next 15 minutes or so.
If anyone is running an upgrade from 3.1 to 3.2, this may help in case you have IO modules that hang.