WCS - AP radio interfaces cannot change Oper Status to up

[markmills]

Hi,

We currently have around 300 1131AG AP's that are being setup in WCS 4.0.96.0

It seems around 30% of them have problems where the OPER STATUS cannot come up.

When going to an AP configuration, and then the Radio interface config, if we try to check the "Admin Status" box so its enabled we recieve the following error:

[ServletException in:/pages/configure/lrad/lradIfDetail.jsp] No collection found'

The config and setup for all the AP's were done exactly the same, so I cannot find any differences between the ones that work, and the ones that do not.

Any suggestions on where to start looking for this is appreciated.

Cheers,

Mark

[claeysg]

Hello Mark,

I had the same issue. It was due to the use of power injectors. Indeed, when a power injector is used, by default, it does not provide enough power to the AP and the radios remain in the DOWN status.

To solve this, you need to go on the controller, then look for your AP and click on details. You will find there POE settings.

You have to select the "override" option.

I have a doc explaining this in details. Give me your email and I will send you a copy of it.

Rgds,

Gaetan

[yprasannas]

Could u please send me the doc to yabalurip@si.edu

[Rob Huffman]

Hi Prasanna,

Power Issue with the AP

When an AP uses a power injector as the power source, in some cases, the AP displays this error message:

CDP_PD-2-POWER_LOW: All radios disabled - LOW_POWER_CLASSIC inline

This message indicates that the AP is in low-power mode with all radios disabled and detects a Cisco switch that is unable to supply sufficient power to the AP. Even though the power injector, which can provide sufficient power, is connected with the AP, the AP still displays a LOW POWER error message and disables the radios. Therefore, the AP remains in low-power mode.

One possible reason for this issue might be that the AP supports the Intelligent Power Management feature. The Intelligent Power Management feature uses Cisco Discovery Protocol (CDP) to allow powered devices, such as an AP, to negotiate with a Cisco switch for sufficient power. The AP supports the Intelligent Power Management feature. As a result of the power negotiations, the AP either enters full-power mode or remains in low-power mode with the radios disabled.

In this case, the AP might be connected to a switch which cannot provide the necessary power to the AP. Therefore, even though the power injector is connected to the AP that uses this Intelligent Power management feature, it gives priority to the CDP information to identify whether or not the switch can provide the power. Once the AP knows, via CDP message, that the switch does not provide sufficient power, it disables the radios and remains in low-power mode.

The workaround to this issue is to tell the AP to ignore the CDP information for power. You can perform this by telnetting into the APs. Issue these commands to enable the APs to use the power injector:

power inline negotiation prestandard source

power inline negotiation injector H.H.H

The power inline negotiation command configures the Cisco Aironet 1130AG or 1240AG Series AP to operate with a later version of switch software that does not support Cisco Intelligent Power Management power negotiations.

The prestandard source portion of the command specifies that the Cisco switch runs a later version of software that does not support Intelligent Power Management negotiations, but is able to supply sufficient power to the AP.

The injector H.H.H portion of the command specifies that a power injector supplies power to the AP, and that the AP connects to a new switch port with the indicated MAC address (H.H.H). Enter the MAC address (in xxxx.xxxx.xxxx hexadecimal format) of the new switch port where the power injector is connected.

Note: This command should only be used when you move an AP and power injector to a different switch port.

From this good doc;

http://www.cisco.com/en/US/products/hw/wireless/ps441/products_tech_note09186a00800a86d7.shtml#new3

Here is the method used via WLC GUI;

http://www.cisco.com/en/US/docs/wireless/controller/4.0/configuration/guide/c40lwap.html#wp1134787

Hope this helps!

Rob