Hi everyone,
I have a full stack of nine 3850 switches in Install mode. The first of which was given priority 15 and I have updated it to the latest 3.7E software. The rest have the IOS-XE version that came from the factory, and are at priority 1.
I configured this stack master to support auto-upgrade.
I am new to 3850s and expected that the auto upgrade feature would work when connecting the other eight to the stack (full ring, i.e. 1st switch to 2nd, 2nd to 3rd... 9th to 1st). After connecting the other eight to the stack, I then powered them on. None of the other eight managed to boot with the IOS-XE version from the stack master. The primary switch's log showed that it recognized the other switches, that there was a version mismatch, and then rebooted them with an auto-upgrade request with an IOS-XE offered by the stack master.
After half an hour of the stack not converging with the same version, many of the other switches had a missing/corrupt IOS-XE version and I had to perform an emergency install via TFTP.
Some things to point out:
1) The stack was cabled so that there wouldn't be a single point of failure (full ring).
2) All switches are the same hardware, same license level and same H/W version.
3) All switches are in Install mode.
I've also tried putting just two switches in the stack (priority 15 and 14), waiting for IOS-XE upgrade and SSO to finish with the stack election, and then connecting the other switches.
Am I not performing this correctly? Should auto-upgrade only be performed one switch at a time to the stack?
Thanks for the help :)
