9

We have two Cisco 2602E APs and one Cisco 3602E AP deployed at a location in China. They are connected to an HP ProCurve 2910al PoE switch.

The 3602E powers up fine when the switch is rebooted (i.e. power loss, they have rolling blackouts in this city) but the 2602E APs both require someone pressing the mode button on them before they power on.

Before the mode button is pressed, the HP switch shows no device on the ports and no power being pulled on them. The APs have no LED activity, they appear off. When someone presses the mode button they mysteriously power on. The HP switch now shows power draw and their LED turns on.

The cable runs to them are around 200'. The switch is PoE+ so it has plenty of wattage to cover any loss over the distance. The 3602 is on a shorter run and has no issues.

We have a second facility in China with the same setup and they do not have this issue. All APs have the same boot loader and IOS per model (i.e. the 2602Es in each site have the same boot loader and IOS rev).

This same issue occurs when using a Cisco 3560C PoE+ switch and the existing cabling setup.

As this is in China, my ability to troubleshoot is a bit limited right now. I am hoping someone has experienced a similar problem and can point me in the right direction. This wouldn't be such a big issue if the APs weren't mounted in a factory ceiling that requires a lift to get to them for pressing the mode button.

What could be causing the 2602Es to not power up with the switch?

4
  • Personally have never heard of this, but that isn't a first by any stretch. Has the cabling been tested & certified, including tests when the run has been connected to the switch to validate PoE? Also, it might be nice to have the output of the console port before they go into this state, during the state and when coming out (if you can recreate) to see if there are any indications.
    – YLearn
    Oct 22 '13 at 5:44
  • The next power outage will be this coming weekend. Should be able to post before and after details then. The cabling was tested - but not for PoE. Next week I have someone going out to swap a 2602 with the 3602 to see if it follows the AP or stays with the port/cabling. Then we'll swap ports if it stays to see if it is the port or cabling. I assume it is cabling but because they tested it for connectivity (not PoE) and re-punched it and put new ends on the patch cables, they won't consider replacing it with shielded cable. Oct 22 '13 at 11:56
  • Are the switches at both sites identical as well? Hardware, firmware revision/OS, and configuration? Can you check the poe status before the APs get manually powered on and see if it's failing in the POE polling? Nov 12 '13 at 22:56
  • Switches are identical. Switches show "Searching" as the status for PoE before the mode button is pressed. Looks like we're waiting on some Cisco 8 port PoE+ switches to add in for the APs, hoping that will resolve it. Nov 13 '13 at 12:26
5

We solved this with new cable runs using STP instead of UTP. No more issues with POE to the APs.

First time we've needed STP and we can't find anything that would cause the interference with the run.

1
  • Thank you for adding the resolution after you spent so much time on the problem
    – This
    Dec 18 '13 at 5:42
0

If some of the pins do not pass cable certification, that could cause PoE issues. Depending on the strand that is at fault, it is feasible that data passes just fine while PoE does not.

Wiki article table showing pins used for PoE: http://en.wikipedia.org/wiki/Power_over_Ethernet#Power_capacity_limits

0

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.