Repeater ssh/web configuration interface not reachable after performing antenna-alignment scan

[dbfokusde]

Hello,

we have a couple of AP1262N-E-K9 APs with firmware version 12.4(25d)JA1 operating in autonmous mode.

One AP is setup as repeater while all others are in root mode.

The repeater has setup one parent MAC address so it associates every time to the same parent root AP.

Given this setting, I am logging into the repeater via SSH and start the antenna-alignment scan:

"dot11 dot11Radio 0 antenna-alignment timeout 4"

During this scan, the repeater disconnects from its parent to perform the scan so no output is visible at the SSH console. After the scan is finished, the repeater re-associates to its parent and some output appears on the SSH console.

Further information is provided in the previous post:

https://supportforums.cisco.com/message/3829096#3829096

The problem:

8 of 10 times this procedure works fine: the scan is finished and I can continue entering commands on the SSH console. However, in some cases the repeater is not reachable any more for about 7 minutes. I.e. pings to the repeater's IP address are unsuccessful and the SSH connection hangs until it is automatically disconnected after a timeout. Also, the web configuration interface is not reachable.

After about 7 minutes everything works fine.

Does anyone have an idea what the cause for this problem is and why it only occurs sporadically? What can be done to solve or at least mitigate this problem?

Thank you for your support! Any idea is appreciated.

[Scott Fella]

Dan,

Why would would run antenna alignment scan on a repeater?  Are you trying to extend coverage over a certain distance?  If so, that can be the issue.  When I have used repeaters way back when, it was only to repeat signals that were maybe <50' due to no cable drop.  If your trying to extend your wireless, maybe look at the WGB feature or do a point to point bridge and use the other radio to serve clients.  Those are better options that repeaters and users can tell the difference when it comes down to throughput.  

Thanks,

Scott

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[Scott Fella]

Here is a WGB configuration example if you want to give that a try.

http://www.cisco.com/en/US/products/hw/wireless/ps430/products_configuration_example09186a00805b9b87.shtml

Thanks,

Scott

Help out other by using the rating system and marking answered questions as "Answered"

[dbfokusde]

Dear Scott,

thanks for the suggestion. It's probably unclear why I am going through all this trouble. So I will try to clarify:

Why do I set up repeater mode and perform the antenna-alignment scan?

Because it's the only way to perform the antenna-alignment scan. I am not interested in running an AP in repeater mode at all. All APs are connected to the wired LAN and thus can operate in root mode.

But why would I need the antenna-alignment scan?

I am going to implement an indoor-positioning algorithm which periodically requires RSSI measurements between all APs. The antenna-alignment scan seems to be the only possible method to obtain these measurements between the Cisco Aironet APs. It came to my attention that the antenna-alignment scan has not been designed for periodical measurements. It has been intended for one-time measurements at the setup phase of the system to find out the optimal position of the antennas. Nevertheless, it has been working considerably well in my recent tests.

Also consider my previous post:

https://supportforums.cisco.com/thread/2188643

Is it possible to run the antenna-alignment scan in bridge/install mode as well? If it worked it might be the better idea as the device would still be available through the wired interface.

I am going to mark the questions as answered when I have found a satisfactory solution :-)

Cheers!

[Scott Fella]

Well wouldn't a WLC solution be you best option?

Sent from Cisco Technical Support iPhone App

[dbfokusde]

It depends on the following question:

When using a WLC and lightweight APs, is it possible to measure the received signal strength between the APs?

It appears to be possible to measure the signal strength of clients connected to the AP. I haven't found any information about measurements between the APs.

[Scott Fella · Accepted solution]

If you run the show run-config in the config analyzer, it will show you adjacent APs and the signal it sees the other APs at.

Sent from Cisco Technical Support iPhone App

[dbfokusde]

Indeed, the config analyzer seems to be a valid solution:

https://supportforums.cisco.com/docs/DOC-1242

However, for some small deployments, it might be too expensive to get a WLC so it would be nice to have a stable method of scanning adjacent APs when operation autonomously.