[ltp] strange behaviour of wireless

[Arno Trautmann]

Hi,

Richard Neill wrote:
> On 08/08/11 08:07, Arno Trautmann wrote:
>> I'm having some trouble with my wireless connection that I don't
>> understand at all; I hope, you can help me even if I cannot offer clean
>> technical details. The machine is X61s with a recent Arch Linux.
>> Description of the symptoms:
>> • Connecting at home to a WEP-encrypted network works, but /only/ at the
>> second attempt. The first attempt to use dhcpcd times out every time,
>> while the second one always works fine and immediately.
>
> One thought: do you have NetworkManager (the system service) running? It
> does things in the background that can sometimes be strange...if you are
> manually configuring with iwconfig/dhclient, you may want to check it is
> off.

No, at least I think it is not running. But to be sure, how can I check it?

>> • Having connected at home once, I am not able to connect to any other
>> network, it just times out everytime. Only rebooting works. This is
>> /only/ after connecting at home; using two other networks is no problem,
>> and from another network to home works, too (again, only the second
>> attempt)
>> • Trying to reboot in such a situation (connecting to another network,
>> timed out) mostly just halts with a message about IRQ #17. However,
>> after the last update, I get a lot more messages. If they are important,
>> I can try to write them down.
>
> You might try one other distro (eg Ubuntu's) live CD (or live USB stick)
> - simply as a way to eliminate whether this is more likely a software or
> a hardware issue.

Will do. (As the X61 doesn't have an optical drive, I have to use an USB 
stick which I never succeeded so far in making bootable …)

>> • Ok, so far I'd just say “stupid Linux, doesn't work” (or rather
>> “stupid user, doesn't configure correctly”). But now comes the part that
>> doesn't make any sense to me: Whenever I connect to my home network, my
>> rommates cannot. In fact, their machines don't even see the radiation
>> any more. As soon as I disconnect, they have excellent signal strengths
>> and connect immediately. When I reconnect, they're out, again.
>>
> Wireless g/b issue? Is it possible that you or they are on 802.11b and
> that this is making the access point switch modes. (Or, for that matter
> g vs a)?

At the moment (at the university) I'm on a 2.462 GHz connection. I'll 
check tonight what channels are used at home. (If that is the 
information you need.)

> P.S. Can you post the relevant bit of lspci?

lspci output:
03:00.0 Network controller: Intel Corporation PRO/Wireless 4965 AG or 
AGN [Kedron] Network Connection (rev 61)

> Are you using a native
> Linux driver, or one of the binary linux blobs, or ndiswrapper?

Not sure; how can I find out?

thanks for your help,
Arno