I agree to Warren. Just to rule out that the upgrade somehow " stuck" I' d take the second unit out completely, boot, format the disk from the boot menu, reload 5.2 firmware via TFTP, reload the config (to set the HA parameters) and reconnect, HA link first.
Sounds complicated but won' t take more than half an hour, and no downtime.
Some precautions:
- make absolutely sure that the slave unit will be secondary on reconnect - set it' s HA priority lower than the master' s.
- of course, save the config of the slave first - do not confuse with the config from the cluster! Easiest would be via TFTP or USB.
- formatting will erase all log files as well (which sometimes is not a real loss)
At least, after this and still seeing the problems, you will know it' s a real bug pertaining to this model.
Ede Kernel panic: Aiee, killing interrupt handler!