You should have checked the release notes for 5.6.3 first to see if your current AP firmware was supported. Then if not (it says 5.4.2 and later) you needed to upgrade APs first.
If you haven't changed the original config on the APs, they should still have 192.168.1.2/24 as a management IP. You can directly hook up your PC/laptop (or via a PoE switch) and use GUI to get in and upgrade them.
Then that was not the problem. What part is exactly not working then? Do you see them in Managed FortiAPs. I guess you still seem them active. Do you see SSIDs you're supposed to see? Are they using the same profile? They might be copied to a "Temp" profile during the upgrade especially when the default profile is used.
But fist of all, did you check "diag debug config-error-log read" to see if any config has been thrown out during the upgrade? You should always check it first every time when you upgraded a FortiGate before, or at the same time, backing up the new config file.
Under "Managed FortiAPs" the STATE is down and no one can connect to it. The AP has an IP address and I can ping it, so I no there are no network issues. I've run execute wireless-controller restart-acd per a KB article, still no go.
Well I figured it out, can't believe it took me this long. For some reason, after the firewall upgrade, the time was off on the Fortigate. This is despite the fact that it is set to get its time automatically from the fortiguard NTP servers. It couldn't contact those servers (maybe because the time was off?) so the date on the fortigate was 1970! Obviously the time must be used the in the DTLS negotiation and that is why they were showing down. Can't believe it took me half a day before I realized the time was off.
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