SG250-26HP - 802.3at PoE+ Issue

Mark Wells · ‎11-21-2016

I have a new Cisco SG250-26HP 26 port Gigabit PoE Smart Switch and 3 new Cisco WAP571-A-K9 V01 the switch supports 802.3at PoE+, 802.3af, however I have never managed to get it to connect at anything other than 802.3af. I have loaded the latest firmware on both with no difference. I have also tried playing with LLDP & CDP but again with no effect.

I was trying to work out if it was the switch not delivering the power, or if it’s the access point not negotiating what it needs, i.e the Access point will run on 802.3af all but with limitations, so fails to get what it actually wants. There doesn’t seem to be the ability to set the switch to use 802.3at PoE+ as default.

Anyone any Ideas on how to solve this issue?

Michal Bruncko · ‎11-24-2016

hi Mark

have you looked on release notes for latest firmware 2.2.5.68? There is list with couple known issues/bugs and possible workarounds. Many of them are related to PoE feature. I recommend you to check that list to see if your issue is related to some of them.

some of the hints:

try to disable "green ethernet" or "eee" features globally or only on ports toward powered device(s)
try to reboot your switch while you keep cable connectivity to powered device to see, if PD came UP once switch reboots back to operable state
what about the "show power inline" while PD is connected to switch? is that PD completely unidentifiable? is status port LED blinking while you connect your device or not?
based on release notes there is possibility to manually set power per each port. you can try to play with it.

Mark Wells · ‎11-24-2016

Thanks for responding Michal

I Have been through the release notes and tried the suggestions, but with no success. I have also had a response from a support case I raised, they indicated that switch is currently not capable of PoE+ 802.3at at the moment and there is no fix! They also mentioned that there was a need for a documentation update.

This seems to imply there is either a bug with the recent firmware releases, or the PoE+ functionality has been removed. I also compared the current configuration options with the ones available on the device emulator, there were a few changes including the lowering of the configurable power from 0 to 6000 to 0 to 15400

I think I will return this switch and look at other options.

Thanks, Mark

Michal Bruncko · ‎11-24-2016

thats really strange if switch is not supporting feature which is in list of switch supported features. this is definitely reason for returning this device.

ddoctorisin · ‎12-22-2016

Same here. Switch only has 100watt Power budget but I get the issue even with only 1 AP WAP571 on it. I have latest firmware on both. I have 10 of these and about 40 of the AP's and Cisco is about to get them all back if they cant' help sort it. 2 hours on the phone with support and the forums has yet to help. 20 SG250-HP Firmware 2.2.5.68 80WAP571 Firmware1,0,0,15

Mark Wells · ‎12-23-2016

I never managed to get the SG250-26HP switch to work, and the only reprocess I got back from Cisco support seemed to indicated that there was an issue with that model of switch, and 802.3at PoE+ had been disabled in firmware.

I sent the switch back under the grounds that I didn’t perform as per specification.

There is the SG250-26P which has a higher PoE power rating, however I could not get a definitive answer if it would work, so I went for the SG350-28P, which worked straight out of the box.