WiFi Clients disconect.

johnleeee · ‎07-23-2007

Hi all,

we have observed the problems with connectivity of our WiFi clients.

Client connect to WiFi network ( we use

AIR-AP1231G-E-K9 and notebooks with its own wifi adapter) and everything is OK.

But after while client disconnects and maybe 5 min try to connect to network but

nothing happens. Maybe after 5 minute interval client connects successfully.

We use WPA/TKIP with domain authentication. Domain accounts.

Any idea?

BR

jl

robert.wright · ‎07-23-2007

Take a look at your logs on your AP(s). Cross reference your ACS/radius logs as well.

Could be a number of issues from the AP(s) loosing connectivity to your ACS/radius, to a constant level of interference which then dissipates. Logs and interface stats will help ya a lot.

'show int dot11Radio0 statistics' will output stats on your radio. when one of these outages occur, review to see if your jammer/energy detct stats are incrementing heavily.

Essentially these two stats roughly tell you theres some sort of RF interference.

johnleeee · ‎07-24-2007

Hi Robert,

I can write command show int dot11Radio0 statistics but I dont know what to do later

and how to resolve our problem.

1.)For example I will see large stats..what I should do ...what is next step?

2.)For example I will not see large stats..what I should do....?

BR

jl

mpatalberta1 · ‎07-23-2007

The WLC will issue multiple RTS message to the target client. The RTS storm can prevent that particular client from connecting and even busy out the Access point. Put sniffer out and see what you are being sent over the air.

From Cisco:

Cisco's position is that the storm occurred because the device on the wired side continued to try to send traffic. If concurrent wired/wireless sniffer trace shows that there was no attempt to send traffic from the wired to wireless side & the AP was doing this on its own, yes.

Otherwise, no.

Development has looked at the sniffer trace for your original concern where there was what appeared to be an RTS storm after your device stopped responding. The conclusion was the controller/AP will continue to try to forward the wired side traffic to the client - for each new packet from the wired side there would be 8 data packet attempts followed by 56 rts attempts.

johnleeee · ‎07-24-2007

Hi Patrick,

thanks for the explanation. We dont use Wireless

LAN Controller, sorry. But on the other hand

could you recommend me how to sniff WiFi?

I know Ethereal. Its good in Win/Linux.

Next, when I will sniff where and what should I be interested in?

Or maybe recommend me how to set up some system to monitor in time traffic ...or some important commands in CLI or...something.

Could problem be in placement of AP itself?

BR

jl