We're using a lot of NetVanta 1238 PoE switches, running AOS R11.4.4 for some reason.
A fairly frequent issue is that the POE system think too much power is drawn and restarts itself:
27-09-2019 13:24:47 Local7.Warning 10.44.30.13 Sep 27 12:24:47 KCNS0502 POWER_OVER_ETHERNET: Total Power Used (6116.007W) has entered the guard band (351W).
27-09-2019 13:24:47 Local7.Error 10.44.30.13 Sep 27 12:24:47 KCNS0502 POWER_OVER_ETHERNET: The PoE hardware has reset, reinitializing...
27-09-2019 13:25:19 Local7.Warning 10.44.30.13 Sep 27 12:25:19 KCNS0502 POWER_OVER_ETHERNET: Total Power Used (33.004W) has exited the guard band (351W).
There's only a few wifi APs on it, so the ~33W is accurate, but that 6116W is just crazy.
Tried to go through the release notes since R11.4, but couldn't yet locate an entry that relates to this.
I'm kinda expecting to be told to just upgrade the switches to something recent, but with change management it'd make life a lot easier if I could just point to a document saying it was fixed in Rxx.yy, so we need to go above that.
ADTRAN, Inc. OS version R11.4.4
Mainline Version: ENM.14.106
P4 Changelist: 208741
Built on: Wed Jul 8 13:23:55 2015
Upgrade key: 48afbdcb1898a8f4565a534afe95b51d
Boot ROM version XB.01.02
Built on: Fri May 25 16:51:16 2012
Compatibility Version: 0
Copyright (c) 1999-2015, ADTRAN, Inc.
Platform: NetVanta 1238 PoE, part number 1702599G1
Serial number LBADTN1230AH611
Flash: 33554432 bytes DRAM: 134217727 bytes
Any pointers much appreciated!
It sure looks like a software bug. No way they're pulling six kilowatts. 11.4.4 is pretty old firmware, release notes for everything between that and current release are long gone from the Adtran site.
I'd upgrade to the latest extended maintenance release. There have been lots of bug fixes in the four years since that software was released.