8086:4220 WiFi (signal strength and connection) drops intermittently: 12.04, Intel 2200BG (ipw2200)

Steve Toub, thank you for reporting this and helping make Ubuntu better.
+ What is the manufacturer and model of the router this laptop has the problem with?
+ Do you have this problem on other routers?
+ If you could also please test the latest upstream kernel available that would be great. It will allow additional upstream developers to examine the issue. Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Once you've tested the upstream kernel, please remove the 'needs-upstream-testing' tag. This can be done by clicking on the yellow pencil icon next to the tag located at the bottom of the bug description and deleting the 'needs-upstream-testing' text. As well, please comment on which kernel version specifically you tested.

If this bug is fixed in the mainline kernel, please add the following tag 'kernel-fixed-upstream'.

If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'.

If you are unable to test the mainline kernel, for example it will not boot, please add the tag: 'kernel-unable-to-test-upstream', and comment as to why specifically you were unable to test it.

Please let us know your results. Thanks in advance.

The bug isn't router-specific. I'm currently using a Linksys E4200 using WPA2 Personal (currently broadcasting as B/G only since broadcasting as B/G/N mixed as more problematic; broadcasting as N tells me my password is bad, which it isn't), but it has been problematic with other routers (Linksys WRT54GS v7, not sure how to determine model numbers for Wifi networks used in the past).

I successfully installed the following kernel:
   Linux ubuntu 3.5.0-999-generic #201207230434 SMP Mon Jul 23 08:42:29 UTC 2012 i68

Things seemed very steady in the first hour or so (no reported variation in signal strength and no dropped connections), even when going back to broadcasting as B/G/N mixed.

However, I'm now seeing the same drops in signal strength and connection drops, so I've removed the 'needs-upstream-testing' tag and added the 'kernel-bug-exists-upstream' tag.

Steve Toub, did this problem exist in prior versions of Ubuntu?

The issue exists in precise and existed in oneric. I haven't tried anything prior to oneric.

I'll add that the intermittency is what's particularly maddening. Sometimes it might disconnect repeatedly in a period of several minutes and then it might go days without disconnect at all. I think I'll bite the bullet and order my friend a new USB wireless adapter.

Let me know if there's more I can do on my end to help provide information upstream. I'm not a developer but I can follow instructions and using a command line.

Thanks for your help so far!

Steve Toub, does this problem occur in a Lucid Live CD?

penalvch, thanks again.

I've been running a Lucid (10.04.4) LiveCD for the last few hours. Signal strength is relatively stable; it does hop around a bit but the lowest I've seen is 40% and it always shoots back up soon after to >95%. It hasn't disconnected yet.

Are there things I can do to stress whatever the possible culprit might be? If 10.04 keeps a reliable connection even through stress testing reinstalling 10.04 may be a viable option for me but I wouldn't want to go down that route unless I was confident this is a lasting solution.

Steve Toub:

>"penalvch, thanks again.

I've been running a Lucid (10.04.4) LiveCD for the last few hours. Signal strength is relatively stable; it does hop around a bit but the lowest I've seen is 40% and it always shoots back up soon after to >95%. It hasn't disconnected yet."

So far so good.

>"Are there things I can do to stress whatever the possible culprit might be?"

I would just do what you would expect you should be able to do in day-to-day use. If it becomes problematic, please doucment this.

>"If 10.04 keeps a reliable connection even through stress testing reinstalling 10.04 may be a viable option for me but I wouldn't want to go down that route unless I was confident this is a lasting solution."

If 10.04 works, then we have a regression that we can further debug. If not, we can work on that too.

Hi Christopher--

10.04.4 (kernel: Linux ubuntu 2.6.32-38-generic #83-Ubuntu) continues to have a steady signal for me (though, ironically enough, as I was typing this message, signal strength went down to 0% a few times, though it didn't seem to disconnect/reconnect)

Let's assume a regression was introduced sometime after this kernel. Can you give me a sense of what I'd need to do from here on out? I've poked around a bit on this today and it seems like the next steps would be for me to:
1. Keep narrowing down which kernel (and eventually, using git-bisect, identify the diffs that) introduced the regression.
2. Submit the properly documented bug report to the kernel-wireless mailing list.
3. Hope the maintainer of the ipw2200 driver takes this on, given all his other priorities.
4. Be available to test any kernel patches.
5. Apply the patched kernel to all kernel updates I accept from Ubuntu until the patch makes it into Ubuntu.

Any shortcuts? ;)

If this was my personal machine I might be inclined to keep going through all those steps, even though it sounds pretty intimidating for a non-developer like me. But this is a friend's machine and the longer I keep it while troubleshooting, the longer she's without a working computer where she is.

Steve Toub, unfortunately, there are no known shortcuts. Assuming a regression, the next step would be to bisect following https://wiki.ubuntu.com/Kernel/KernelBisection . If you know you cannot go farther than what you have done, I would just back up her data, install Lucid, and give the PC back. This will give her 9 months until Lucid EoLs https://wiki.ubuntu.com/Releases .

Ok, thanks again, Christopher, for the professional and helpful service you have provided me and others.

Feel free to close this bug since I don't plan on doing any more to address the root cause.

I spent half the day on 10.04 and it remained steady but then I was wondering if that was just dumb luck so I switched back to 12.04 and that was steady as well. I tried to stress the wireless connection by transferring a large file while surfing but it even remained steady through that. It just won't break when I want it to. ;)

Anyways, I want to get the machine back to my friend in the next few days, so I bought a USB wireless card and hope that does the trick. (Though if I can things to break again truly verify that 10.04 is indeed better than 12.04, I'll install 10.04.)

For others who have the same issue, note that https://bugzilla.kernel.org/show_bug.cgi?id=15813 is the only reference to this issue with this driver that I could find in the Kernel Bug Tracker. I found a couple of other kernel bugs with similar issues but with other devices/drivers:
 https://bugzilla.kernel.org/show_bug.cgi?id=42877 is with the ath9k driver
 https://bugzilla.kernel.org/show_bug.cgi?id=43123 is with the iwlwifi driver