Users getting dropped sessions on wireless

[Brandon Koehler]

I've posted about this previously, and the past answers that were provided did help, but I'm still getting users complaining about Citrix and RDP sessions getting dropped.

We've got a WLC 4402 with 15 1142n APs, spread out on multiple floors. The 4402 is basically set to defaults. Users don't have be moving to experience drops, although that happens as well. One user was dropped 4 times in the span of 1 hour yesterday, and his computer never left his desk.

Most frustratingly, our hosting company does not support Citrix session reliability, so if the Citrix session disconnects, the user is forced to start the application from scratch, losing any data that was typed in.

The users all have Intel Wifi Link 5100 wireless cards, with the power saving features shut off.

WCS doesn't show anything strange for the users when they get dropped, most of the time, they've been connected to a single AP for the entire day, up to that point, whether it's 10 minutes or 6 hours.

thanks in advance for any help.

[Surendra BG]

Hi,

Whats does the debug or the msg log or the trap log say when the client faces the issue??

Regards

Surendra

[Brandon Koehler]

Thanks for the reply. I must admit that I am a bit inexperienced in regards to Cisco wireless. How do I view the logs you mentioned?

[Surendra BG]

Hi,

On the WLC GUI u will be able to see msg logs and trap logs.. and run the debug "debug client , reproduce the issue and attach it here..

Regards

Surendra

[Brandon Koehler]

That's kind of the problem, I can't reproduce the issue. It's very random. Is it a bad idea to run the debug on a single client for a few hours and hope they get dropped?

[Surendra BG]

To get the root cause, then we need to do this..

Regards

Surendra

[Brandon Koehler]

Okay, I hate to say it (because I do work tech support, and hate it when users can't find the plainly obvious button on their screen), but I can't seem to find the area to run the debug on a single client, both in our WLC, and in our WCS. We're running the latest versions of both.

In the WLC, under Management -> Message logs, the box in there has a ton of errors like this:

*Dot1x_NW_MsgTask_0: Apr 01 13:03:05.230: %DOT1X-3-INVALID_WPA_KEY_MSG_STATE: 1x_eapkey.c:708 Received invalid EAPOL-key M2 msg in START state - invalid secure bit; len 24, key type 1, client 00:26:c6:ad:be:5

As well as a few like this:

*spamReceiveTask: Apr 01 13:06:56.173: %LWAPP-3-REPLAY_ERR: spam_lrad.c:23862 Received replay error on slot 0, WLAN ID 1, count 1 from AP 00:26:cb:a1:09:e0

or:

*apfProbeThread: Apr 01 13:02:29.124: %LOG-3-Q_IND: 1x_eapkey.c:708 Received invalid EAPOL-key M2 msg in START state - invalid secure bit; len 24, key type 1, client 00:26:c6:ad:96:50

Under Config, Buffered Log Level is set to Errors, and Console Log Level is set to Disable.

Thanks for any help

[Brandon Koehler]

Some new information on this that pretty much makes this our hosting company's problem. Unbeknownst to me, many of our wired users were experiencing the same problem, ie, working along in Citrix, and then getting booted out.

Oddly, none of our RDP users in the same host are experiencing the problem.

But this isn't a wireless problem, and I'm relatively sure that it's not a network issue, either.

Thanks for the help.

[phamquoccuong]

Anyone resolved this problem yet? I have the same errors logs as Brandon Koehler.

Thanks for any help!

[Brandon Koehler]

I later started a support call with Cisco, and they determined that there must be a bug or something in Microsoft Windows 7. Disabling Fast Reconnect in the wireless properties does help a little bit, however, you'll still get the occasional drop when clients roam between APs. Since I don't have a support contract with Microsoft, I wasn't able to go any further.

However, according to Cisco, dropping down to WPA (vs WPA2) and using Cisco's key managment system (can't remember what the actual acronym is right off the top of my head) that is built into the full Intel wireless client should fix this problem. As a medical facility, I decided that I couldn't take the risk of WPA (no matter how remote).

Good Luck!

[phamquoccuong]

Hi Brandon,

Thanks for your reply. I should try disabling Fast Reconnect first. Then try to find another solution.

Have a nice day!

[awiranata]

Hi,

I have some issue

Any another one solved this issue?