Upgrade time estimate for 9800LC controller, 17.6.3 to 17.9.3

[MauryJ]

Hello all,

I'm planning to upgrade our 9800LC (physical) controller from 17.6.3 to 17.9.3. 

The release notes mention that the upgrade should complete in under 6 hours for a large network.  We have about 30 C9115AXI-B AP's.   How long should we expect the upgrade to actually take?   Also if anyone has taken this upgrade path, did you run into anything that needed to be corrected post-upgrade?

Thanks

[Leo Laohoo · Accepted solution]

Depending on the method.  

If I use my one-hit-wonder, the WLC will take 8 minutes. 

This outage time does not include the additional time for the APs to download the firmware and boot up.  

[Rich R · Accepted solution]

If you pre-download the APs then most of them should be back within minutes of the WLC upgrade (they just switch image and reboot).  Inevitably there are a few that insist on downloading again after the upgrade but there's nothing much you can do about that.  Of course you should always plan the upgrade for "out of hours" and give yourself at least an hour window for checks and troubleshooting any APs that don't return immediately.  Sometimes you might need to power cycle an AP to kick it back into life.