Infinite loop: Wifi connects, disconnects and then tries to reconnect

rm_-rf_windows · 11-01-2012, 04:02 PM

Hi all,

I have a netbook which I use frequently in different contexts and with many different wifi networks. I generally do not have problems connecting to wifi networks.

At work, when I try to connect to the wifi network, it connects and then immediately disconnects and tries to reconnect again. I don't understand why, and unfortunately I don't know enough about networking to give more clues, perhaps someone could give me a hand to diagnose the problem. I know that this only happens on my netbook on Ubuntu, others who use the network have no problems. At one point (some time ago) it worked fine and then started acting up and has never been normal since.

It seems that sometimes I connect and then immediately when I run a Google search or try to load a webpage it disconnects and tries reconnecting again. It's strange and quite irritating.

The only thing I can tell you is that it is WPA2 and that this even happens when the signal is extremely strong.

If you need any more info, I'd be glad to run some commands or copy and paste log files here. I really have no idea where to start.

I'm on Ubuntu 10.04.4 LTS (lucid). I'm using both Wicd Network Manager and Network Manager Applet.

Thanks in advance,

rm

frankbell · 11-02-2012, 08:35 PM

If the problem happens only with your workplace network, I'd start with the IT folks there, as it is the odd man out. Maybe they changed something.

This article has some good general hints: http://www.cyberciti.biz/tips/linux-...ose-tools.html

You might check your log files, in particular /var/log/messages. I'd recommend using the tail command right after a network failure, like this (the example will display the last 1,000 lines of the file):

Code:

tail -1000 /var/log/messages

You can also watch the logs in real time with the -f argument. This article gives some examples: http://www.cyberciti.biz/faq/howto-g...-unix-logfile/

Run the command in a terminal and leave it running, then attempt to connect. The output to the terminal might tell you something.

rm_-rf_windows · 11-03-2012, 01:46 PM

Many thanks frankbell for your reply.

I cannot ask about the network given that I'm using it unofficially. Also, there are many clients who use the network regularly and nobody has any of the problems I have been having. Also, it works on my other laptop. (It is not an IT company network)

Here's what's at the end of the log file when I try to connect, I don't know if this is of any help:

Code:

Nov  3 19:20:40 user-netbook kernel: [701239.955137] ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
Nov  3 19:20:52 user-netbook kernel: [701251.109589] type=1503 audit(1351966852.137:77):  operation="open" pid=18097 parent=18032 profile="/sbin/dhclient3" requested_mask="r::" denied_mask="r::" fsuid=0 ouid=0 name="/var/lib/wicd/dhclient.conf"
Nov  3 19:21:05 user-netbook kernel: [701264.263179] ADDRCONF(NETDEV_UP): wlan0: link is not ready
Nov  3 19:21:05 user-netbook kernel: [701264.485625] ADDRCONF(NETDEV_UP): eth0: link is not ready
Nov  3 19:21:10 user-netbook kernel: [701269.083575] ADDRCONF(NETDEV_UP): wlan0: link is not ready
Nov  3 19:21:10 user-netbook kernel: [701269.114842] ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
Nov  3 19:21:16 user-netbook kernel: [701275.230925] ADDRCONF(NETDEV_UP): wlan0: link is not ready
Nov  3 19:21:16 user-netbook kernel: [701275.417669] ADDRCONF(NETDEV_UP): eth0: link is not ready
Nov  3 19:21:16 user-netbook kernel: [701275.574918] ADDRCONF(NETDEV_UP): wlan0: link is not ready
Nov  3 19:21:18 user-netbook kernel: [701277.945067] ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
Nov  3 19:21:31 user-netbook kernel: [701290.217139] type=1503 audit(1351966891.246:78):  operation="open" pid=18311 parent=18214 profile="/sbin/dhclient3" requested_mask="r::" denied_mask="r::" fsuid=0 ouid=0 name="/var/lib/wicd/dhclient.conf"
Nov  3 19:21:48 user-netbook kernel: [701307.279194] ADDRCONF(NETDEV_UP): wlan0: link is not ready
Nov  3 19:21:48 user-netbook kernel: [701307.489232] ADDRCONF(NETDEV_UP): eth0: link is not ready
Nov  3 19:21:53 user-netbook kernel: [701312.082285] ADDRCONF(NETDEV_UP): wlan0: link is not ready
Nov  3 19:21:54 user-netbook kernel: [701313.124743] ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
Nov  3 19:21:54 user-netbook kernel: [701313.914318] ADDRCONF(NETDEV_UP): wlan0: link is not ready
Nov  3 19:21:55 user-netbook kernel: [701314.105881] ADDRCONF(NETDEV_UP): eth0: link is not ready
Nov  3 19:21:55 user-netbook kernel: [701314.262241] ADDRCONF(NETDEV_UP): wlan0: link is not ready

Does this provide any clues?

Sometimes I get a connection for a few seconds or even a minute or so, but then it disconnects and then "Unable to connect" is displayed in my navigator. Or, wifi connection okay (icons indicate so), but "Unable to connect" or "Server not found" appears in navigator. Or, the connection can come and go. For example, I had to struggle for almost a half hour to post this message (to cut and paste the above and send it from the very netbook that has trouble connecting).

Many thanks,

rm

frankbell · 11-03-2012, 08:49 PM

My attention is drawn (how's that for a pretentious phrase?) to the "denied_mask" statement.

I googled around for about 15 minutes and couldn't find any kind of explanation that I was able to understand for this string:

Code:

type=1503 audit(1351966891.246:78):  operation="open" pid=18311 parent=18214 profile="/sbin/dhclient3" requested_mask="r::" denied_mask="r::" fsuid=0 ouid=0 name="/var/lib/wicd/dhclient.conf"

I'm confident that the answer lies in there somewhere, but it's beyond my experience.

Hopefully someone will come along and enlighten both of us.

frankbell · 11-03-2012, 10:24 PM

I posted the line of text listed above to newly-instituted forums for my LUG.

One of the members suggested checking the permissions for /var/lib/wicd/dhclient.conf. He points out that in Slackwere (he's a Slacker), they are normally 755 and thinks the problem may lie there.

rm_-rf_windows · 11-04-2012, 02:33 AM

Hi,

Code:

-rw-rw-rw-  1 root root  927 2012-11-04 08:23 dhclient.conf

Two more clues:

Same results in all browsers
This only happens with the one wifi network. When I'm elsewhere (anywhere... hotels, etc.), this never happens, or perhaps extremely rarely

rm_-rf_windows · 11-10-2012, 02:30 PM

Idea:

Is there a way of completely reinitializing my wifi setup (all configuration files, all! Everything!!)?

That might solve the problem.

rm

frankbell · 11-10-2012, 08:04 PM

I went back and saw you said you are using both nm-applet and wicd. Try removing one of them. If you have both, only one of them is making the connection; the other is just mirroring the other. Trying to use both does not help; I speak from experience.

Also, try testing it with a Live CD of something. First, test the Live CD at home to make sure it sees your wireless connection reliably. When you verify that it does, then try it at work.

This will help you determine whether it's the software load on your computer or something larger.

rm_-rf_windows · 11-11-2012, 02:41 PM

Many thanks again for your post.

I have tried disabling one. Apparently if you have both it doesn't present a problem.

If I hook up another wifi card (usb wifi card) to my NetBook and use it, I have no problem whatsoever.

As I said, I use my netbook all over the place. I've used it at over 100 wifi hotspots (same setup, same user account each time). I only have this problem with the one network.

I'd like to just reset my entire wifi setup so that it works like new... Would you or anybody know how to do that? I don't mind reentering all of the passphrases...

Many thanks for your efforts frankbell!

rm

frankbell · 11-11-2012, 07:48 PM

I've never done that, so I hesitate to offer advice. This thread from the Ubuntu forums might help.

http://ubuntuforums.org/showthread.php?t=1901614

rm_-rf_windows · 11-12-2012, 01:48 PM

Thanks frankbell for your efforts.

If I find a solution, I'll be sure to post it here.

rm