Cisco 1810W drawing 24.5W on Cisco 3650 PoE Switch

[jerrysafetynet]

Hello,

     I have a network with 350 Cisco 1810W access points that are connected to Cisco 3650 PoE switches.  I have noticed that the APs are drawing almost the full 30W per port.  I believe these APs should only be drawing 8 to 10W while in normal operation and I think they were when they were first installed. This is casing a problem now as the switches are hitting their limit on PoE budget.  These APs are being controlled by a WLC 5520 with 8.3.130 firmware.  I have tried to manually set the ports on the switch to only use 15.4W, but I get an error saying "power denied".  Any help with this would be great.   Thank you.

[Rich R]

What is the full error message you're getting in the log?

[jerrysafetynet]

May 18 21:16:12.507: %ILPOWER-5-ILPOWER_POWER_DENY: Interface Gi1/0/9: inline power denied. Reason: insufficient power
*May 18 21:16:27.514: %ILPOWER-5-IEEE_DISCONNECT: Interface Gi1/0/9: PD removed
*May 18 21:16:28.511: %ILPOWER-5-DETECT: Interface Gi1/0/9: Power Device detected: IEEE PD
*May 18 21:16:28.513: %ILPOWER-5-ILPOWER_POWER_DENY: Interface Gi1/0/9: inline power denied. Reason: insufficient power
*May 18 21:16:43.520: %ILPOWER-5-IEEE_DISCONNECT: Interface Gi1/0/9: PD removed
*May 18 21:16:43.998: %ILPOWER-5-DETECT: Interface Gi1/0/9: Power Device detected: IEEE PD
*May 18 21:16:44.001: %ILPOWER-5-ILPOWER_POWER_DENY: Interface Gi1/0/9: inline power denied. Reason: insufficient power
*May 18 21:16:59.009: %ILPOWER-5-IEEE_DISCONNECT: Interface Gi1/0/9: PD removed
*May 18 21:17:00.522: %ILPOWER-5-DETECT: Interface Gi1/0/9: Power Device detected: IEEE PD
*May 18 21:17:00.523: %ILPOWER-5-ILPOWER_POWER_DENY: Interface Gi1/0/9: inline power denied. Reason: insufficient power
*May 18 21:17:15.529: %ILPOWER-5-IEEE_DISCONNECT: Interface Gi1/0/9: PD removed
*May 18 21:17:16.519: %ILPOWER-5-DETECT: Interface Gi1/0/9: Power Device detected: IEEE PD
*May 18 21:17:16.521: %ILPOWER-5-ILPOWER_POWER_DENY: Interface Gi1/0/9: inline power denied. Reason: insufficient power
*May 18 21:17:31.527: %ILPOWER-5-IEEE_DISCONNECT: Interface Gi1/0/9: PD removed
*May 18 21:17:32.529: %ILPOWER-5-DETECT: Interface Gi1/0/9: Power Device detected: IEEE PD
*May 18 21:17:32.531: %ILPOWER-5-ILPOWER_POWER_DENY: Interface Gi1/0/9: inline power denied. Reason: insufficient power

[Rich R]

Then it's starting to look like you also have a bug in the switch IOS!  What version is it?

We can see your AP requested these power levels: Power request levels are:24500 15400 0 0 0

So with that setting the switch *should* have granted 15400 but it seems to be ignoring that and just denying the 24500!

There are a number of bugs like this https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvq65075 for switch stacks doing this incorrectly.

Workaround: Reload of the switch stack should solves the issue.

So might be worth trying a switch reload?

But really the solution is upgrading to fixed WLC software ...

[Leo Laohoo]

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@jerrysafetynet wrote:

*May 18 21:17:32.531: %ILPOWER-5-ILPOWER_POWER_DENY: Interface Gi1/0/9: inline power denied. Reason: insufficient power

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Read the logs very, very carefully.  PoE power is denied because there is not enough power allowance left.  

1. Show us the config of the port Gi 1/0/9
2. The AP requires >24.0w PoE.  What are you trying to accomplish with manually configuring the power to 15.4w?
3. Did you shut/no shut the port?

[jerrysafetynet]

There is 171.3 Watts available on the switch with ports 1-10 disabled.  A Cisco 1810W (small wallplate AP) needs 24W of PoE to run?  That's seems way too high.  I have 1832's and 2800's at the site that are drawing less power.  I do have 1810W at other sites connected to HP/Aruba switches and they are only drawing between 3 and 5W.  I did also try setting the static max power to 24000 and I still get the power-deny error. I was hoping by setting it to only 15.4 we would stop running into the maxing out the PoE budget on the switch.  Right now we can't fully power all the APs connected to the switch.   I really appreciate the help. Thank you for looking into this.

[jerrysafetynet · Accepted solution]

We were able to get the firmware and upgraded the WLC to version 8.5.151 and now the APs are showing at 14.5w.  still seems high but it's allowing us to add more APS to the switches like we needed.  Thanks everyone for you help.