Ok, here is what I have right now:
$ uname -a
Linux ljutntcol 2.6.38-15-generic #59-Ubuntu SMP Fri Apr 27 16:04:29 UTC 2012 i686 i686 i386 GNU/Linux
$ cat /etc/issue
Ubuntu 11.04 \n \l
$ lspci | grep Wireless
01:00.0 Network controller: Atheros Communications Inc. AR9285 Wireless Network Adapter (PCI-Express) (rev 01)
Same problem as everyone else - wireless keeps dropping (for me, with the wireless connection at work), where
tail -f /var/log/syslog typically will report:
NetworkManager: <warn> (wlan0): link timed out.
I have even had the situation where I held my netbook like maybe 50 cm away from a relatively new Cisco wireless node at work - and it would still keep on disconnecting! However, strangely, at home, I have no problems whatsoever being on the wireless; possibly because at home I have just a plain WEP authentication; but at work I have to use 'PEAP with TKIP/MSCHAPV2'.
Anyways, first I tried installing
linux-backports-modules-cw- as @sokai and @dhojgaard recommended; by this time, there is now for Natty (11.04) the 3.0.0 version, so I tried:
$ sudo apt-get install linux-backports-modules-cw-3.0.0-natty-generic
The following NEW packages will be installed:
... and rebooted - but no dice, still link would time out. So I did:
$ sudo apt-get remove --purge linux-backports-modules-cw-3.0.0-natty-generic
$ sudo apt-get autoremove --purge
Then finally I found this thread, which refers to a bug related to my wireless network adapter:
Within this thread, there is a recommendation to use
wicd - which is something like a network manager (along with a GUI) for wireless stuff.
So I did:
$ sudo apt-get install wicd
and then rebooted - then both NetworkManager and
wicd GUI applets are started and shown in toolbar.
However, for one, it seems
wicd cannot work with NetworkManager running in the background; some people remove network-manager - but I found it easier to just stop it:
$ sudo service network-manager stop
... and this causes the toolbar GUI icon to disappear as well.
So, at this point, I can choose "Refresh" from "Wicd Network Manager" GUI, and the networks are being scanned and found. Note that there is a separate
$ find / -xdev -name 'wicd*' 2>/dev/null # to find the log file
$ tail -f /var/log/wicd/wicd.log
... and I also observe at the same time
tail -f /var/log/syslog.
Now at this point, I try to connect to the work wireless network, but I cannot get it to connect, and
wicd in the log complains about bad password (which was definitely correct):
2012/05/15 10:14:07 :: iwconfig wlan0
2012/05/15 10:14:08 :: WPA_CLI RESULT IS ASSOCIATED
2012/05/15 10:14:09 :: WPA_CLI RESULT IS ASSOCIATED
2012/05/15 10:14:09 :: iwconfig wlan0
2012/05/15 10:14:10 :: WPA_CLI RESULT IS ASSOCIATED
2012/05/15 10:14:11 :: wpa_supplicant authentication may have failed.
2012/05/15 10:14:11 :: connect result is Failed
2012/05/15 10:14:11 :: exiting connection thread
2012/05/15 10:14:11 :: Sending connection attempt result bad_pass
2012/05/15 10:14:11 :: ifconfig eth0
2012/05/15 10:14:11 :: ifconfig wlan0
2012/05/15 10:14:12 :: Forced disconnect on
2012/05/15 10:14:12 :: iwconfig wlan0
However, at this point, I realize that whenever a connection is attempted, something called
vpnagent appears in
kernel: [ 146.999858] wlan0: associated
vpnagent: Function: tableCallbackHandler File: RouteMgr.cpp Line: 1694 Invoked Function: recv Return Code: 11 (0x0000000B) Description: unknown
Then I check in the process list:
$ ps ax | grep vpn
2539 ? S 0:01 /opt/cisco/vpn/bin/vpnagentd
... and finally I remember - this was a Cisco VPN client that we had to use to connect to work VPN network... what I wasn't aware off, however, was that the VPN client actually installs a service/daemon, which runs in the background, and is started at boot!
So, I kill the vpn service:
$ sudo killall vpnagentd
... and I re-run the 'Connect' button on the desired networ in Wicd Network Manager GUI - and FINALLY I get to connect to the network!
Actually, I'm writing this using
wicd - and the wireless network even 'fell' once (quote a bit of users, and signal is not strongest) - but
wicd reconnected without a problem!
Well, I hope at least that this solves my wireless woes - and that this may help others,