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New Member

AIR-AP1242AG Dot11 0 Radio in Reset mode.

I have a few of these, brand new, just attached them to the network using AIR-PWRINJ3's. The radios are disabled with the following error:

"CDP_PD-2-POWER_LOW: All radios disabled. LOW_POWER_CLASSIC_NO_INJECTOR_CONFIGURED"

This is the right power injector, it works with 2 out of 6 new 1242s...

Any ideas?

8 REPLIES
Hall of Fame Super Red

Re: AIR-AP1242AG Dot11 0 Radio in Reset mode.

Hi Allen,

I think you are running into this issue because the 1242 AP supports the Intelligent Power Management feature (which I didn't even know existed until now). Have a look at the following.

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/ps430/products_tech_note09186a00800a86d7.shtml#new3

Hope this helps!

Rob

Please remember to rate helpful posts.....

Silver

Re: AIR-AP1242AG Dot11 0 Radio in Reset mode.

Also worth noting, if you are using 4.x on the controller you can now configure this directly from the controller. Under the access point configuration there is a check box for "pre-standard state" and "power injector state". Unfortunately, this is not yet available on WCS, so AP templates will not help deploying this to multiple APs yet.

New Member

Re: AIR-AP1242AG Dot11 0 Radio in Reset mode.

Yeah I saw that article too. I tried the command, reloaded and they are still in reset.

I might try disabling CDP to see if that lites up the radio. Or it could just be bad Power Injectors.

New Member

Re: AIR-AP1242AG Dot11 0 Radio in Reset mode.

Disabling CDP (no CDP run) was the only way to get the radios to come online...

Silver

Re: AIR-AP1242AG Dot11 0 Radio in Reset mode.

You could also just to no cdp enable on the ethernet ports going to your APs. That way you don't have to disable CDP globally.

New Member

Re: AIR-AP1242AG Dot11 0 Radio in Reset mode.

Hall of Fame Super Red

Re: AIR-AP1242AG Dot11 0 Radio in Reset mode.

Hi David,

Thanks for posting up the new link :) I don't know why Cisco has to move these around so much. Every time I find a good link and bookmark it, the next time I go to use it, poof!! It's not available :( 5 points for your good work here!

Take care,

Rob

New Member

thanks, Rob,it helped me out

thanks, Rob,it helped me out of the problem.

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