(Wireless) Disassociated because sending station is leaving BSS

[johnnymc]

I have a cisco 1231 WAP that averages 4 clients per hour on it. The clients get kicked off and on all day. I tried switching from the windows wireless client to the intel client but that had no effect. I pulled the 1231 and put in a new 1100 series and got the same thing. IOS version is 12.3.7JA. Here is what I see in the log:

Interface Dot11Radio0, Deauthenticating Station 0015.0013.8fa2 Reason: Disassociated because sending station is leaving (or has left) BSS

Has anyone seen this before?

 

[vipergg]

Sounds just like the clients are roaming out of reach of the wap.

 

[johnnymc]

The users are always within 20 feet of the WAP so I dont think they are walking out of range of it. I tried upgrading the IOS to 12.3.8 but that did not seem to help.

 

[JOAMON]

Look for other sources of interferance. 2.4 ghz phones are notorious for interferring with 2.4 ghz access points. Suggest changing to 5.8 ghz or 900 mhz if this is a problem. Also take a look at the config and maybe consider turning up the gain on the antennas.

 

[bugmn99]

I see the same log entry when I either roam to another AP or disable my wireless NIC. Try doing a little 'War-walking' around the wireless footprint while logged into your AP and repeatedly issuing the 'show dot11 associations all-client' command (or 'sh dot assoc all'). Know your client's wireless NIC's MAC address and watch for it in the output. It'll give your client's signal strength and quality as well as some other useful packet information. While doing this, also keep an eye on your laptops signal strength in the system tray. See what movement/distance causes it to get weaker. Hopefully it'll be just a matter of re-positioning the AP. However, you may end up having to play around with the gain settings, like JOAMON said.

 

[voltron1011]

Yup, sounds like you've got some interference issues. There has to be something around there that is effectively jamming your AP.

 

[johnnymc]

I cant seem to find any other signal that would disrupt the 1200 WAP. I placed a laptop 2 feet from the WAP and after an hour and a half it dropped the signal for 13 seconds and then reaquired but another client that was roughly 15 feet away didnt drop the signal...

My next question is, is the anntenna what makes the signal 2.4 or 5 Mhz? if so I can buy a new antenna and try a different freq to see if tha clears it up

 

[JOAMON]

802.11 B & G operate on 2.4 GHZ. 802.11 A is 5 GHZ.

 

[johnnymc]

crap, so I cant just go out and buy a new antenna hoping to get a different freq.

 

[JOAMON]

Use the web browser and check the detailed settings for the radio interface and make sure it is set to:

Default Radio Channel: Least Congested Frequency

That way it will automatically select the least congested channel.

 

[johnnymc]

I have had it set like that most of the time. Today to experiment I have been picking freq's and leaving them on for a few hours to see if I still get the drops. I still do, they seem random. I removed the 1200 wap and put in a 1100 wap and got the same results. I now have the 1200 on one end of the hall and the 1100 on the other. I still see random drops.

 

[JOAMON]

Are these random drops from the same machine? If so I would begin to think maybe it is something with the laptop. Have you thought about downloading network stumbler just to see what else is out there?

 

[johnnymc]

Different machines drop off at random times, heres an example from the log:

11:30 - 1d0a connects
11:45 - afe8 connects
12:01 - 8fa2 connects
12:46 - 8fa2 drops connection
12:50 - 0o18 connects
12:52 - afe8 roams to another wap
12:54 - 0c18 drops connection
13:19:43 - 1d0a drops connection
13:19:56 - 1d0a connects

 

[JOAMON]

You might consider the following:
Check the wireless laptop. Go into properties and on the wireless tab you see your preferred network in the preferred network list. Click on the advanced button and make sure the box for automatically connect to non-prefferred networks is not checked and should also be set to infrastructure mode. In the browser setup for your access point click on security and then ssid manager. At the very bottom you select your infrastructure ssid and can also force infrastructure devices to only associate with your ssid.

 

[JOAMON]

I also recommend getting network stumbler and taking a look to see what else is in your area. It is a free download.

http://www.netstumbler.com/downloads/

 

[voltron1011]

We use a program on all our laptops called Atheros that gives you much more control than the XP wireless one. You can configure multiple Profiles like (home, work, MIS work group, etc). It will stop XP's habit of searching for different WAP's.

 

[JOAMON]

Still have a look with network stumbler....it may reveal another source of disruption.

 

[johnnymc]

Thanks for all the input. I have tried using the intel pro wireless client but it made no difference. I will check out stumbler today as well as atheros and let you know me results