Symptom

All APs disconnected at same time from WLC1 and moved to WLC2 for hitless upgrade process using GUI Aps failed to predownload image due to /tmp full

Conditions

Observed when doing hitless upgrade from GUI between WLCs running 17.12.4 and 17.12.5 Issue is triggered by APs failing to do predownload due to AP /tmp been full CSCwm08044 - APs unable to upgrade without a power cycle : Error: unlzma: write: No space left on device

Workaround

Reload APs to clear /tmp Check AP show filesystem before preodownload to check if AP needs to be reloaded before starting process

Further Problem Description