Question: Why are APs on SPOE ports simultaneously rebooting at random times when they are directly connected to an Aruba controller?
Product and Software: This article applies to the Aruba 800, Aruba 2400, and LC-2G24F with SPOE hardware.
The Serial Power Over Ethernet (SPOE) port supplies power to an AP when the AP responds with the correct resistance signature. Sometimes another POE switch detects the Aruba controller as a POE client and then sends foreign power toward the controller. The solution for this behavior is to use a cross-over cable and to disable POE on the ports of both switches. This solution prevents the POE logic on the controller from resetting the APs.
A POE conflict was recently determined to be the power supply of an Aruba AP-80M. This POE conflict triggers the detection of a foreign voltage and resets all the directly connect APs to a SPOE port. The exception is the AP-80M that was using an external power supply. The solution for an AP-80M, AP-80SB, or AP-80MB power supply that sends power to a SPOE interface is to move the AP to a core switch.
In summary, remove all directly connected POEs or power sources. If all the power sources have been eliminated and the problem still occurs, review the issue with Aruba support for a possible RMA.