Do you have a reliable UPS protecting it? I wonder if you are looking at a transient power glitch. But if the unit is under maintenance, I would definitely call Extreme.
Choose a time when the stack can be down. Take one switch out of the stack ("disable stacking node address xx:xx:xx:xx:xx:xx") which will reboot into factory default mode. Loop the stacking cable, then run stack port diagnostics ("run diagnostics...
I came over from Cisco and had little trouble making the switch. Read existing configuration files to get started, and download the documentation - both Concepts / User guide (name depends on firmware version) and Command Reference. When dealing...
