Wireless stops working but says it is connected

I've been having similar issues too. I'm connected for a while and then suddenly nothing works even though the wireless app in the top right (NetworkManager) shows I still have bars and a connection. If I look at ifconfig I see that I no longer have an IP address on my wireless adapter. A reboot usually fixes it.

What I've noticed is that in my case it seems to be related to broadcom wifi adapters. My laptop with an intel wifi doesn't exhibit this behavior.

What wifi do you have? If you are not sure, open a terminal and run

lspci

and look for the line referring to your wifi.

As for a solution I don't have one yet. However, knowing that others are having a similar problem points at a possible bug.

The line that seems most relevant to wifi when I run lspci is this:
"02:00.0 Ethernet controller: Marvell Technology Group Ltd. 88E8056 PCI-E Gigabit Ethernet Controller (rev 12)
"
It's a wireless antennae that plugs into my motherboard.

Interestingly; it looks like I still have an ip when mine stops working, but on the other hand I'm not entirely sure what I'm looking at so could be wrong.

Hmm, maybe it's just a driver issue (for both of us). I have no experience with Marvell cards but you might explore using a newer driver. It seems there are some linux ones here - http://www.marvell.com/drivers/search.do

I've been testing it a lot and It seems that it cuts out almost always when I'm downloading files from many peers at once. This makes me think that it's either:
1) the number of connections; or
2) the amount of data transfer
that's causing it to crash. I'm not sure, but that's what seems to be the problem. Now I just need to find out which is the issue and how to fix it...

That's a reasonable conclusion but if so it still points to a driver issue. Unless there is something physically wrong with the card, any issues you are having are almost certainly driver related. Unfortunately, wifi in Linux is a bit of a sore spot. I would check the marvell site and see if you can find an updated and Linux specific driver to try.

A somewhat roundabout approach and maybe not very useful depending on where you live would be to buy a new wifi card (one with great Linux support) and try it. Many big name stores will let you return stuff but that would help you narrow down if it's a problem with your specific card or something broader.

However, I'd be willing to bet a different driver, assuming one is available, would solve the problem.

Ok, well I went on that site you linked and searched by my product number. It's given me a whole list of different drivers for different platforms and, rather embarrassingly, I don't know which platform is relevant to me (I'm still quite new at this Ubuntu lark!).

I'm running Ubuntu 8.04, could you give me an insight?
Thanks a lot for your help so far, by the way!

Here's the link for the results for my product number (88E8056) by the way:
http://www.marvell.com/drivers/driverSearchResults.do?currentPage=1&searchType=2
Apologies of that doesn't work.

I can't promise this is correct but my thinking is that the second option for linux 2.4.20+ would work as 8.04 is certainly above that and that driver is fairly new as well. Nothing else there is appropriate. The last one says for kernel 2.6.x which is actually the kernel used in Ubuntu 8.04 but it also says for Yukon devices and I have no idea what that means so I would not suggest using that.

Well I tried that one you suggested, as well as all of the other linux ones and I always get this same problem:

squisher@squisher-desktop:~/Desktop/DriverInstall$ sudo ./install.sh
[sudo] password for squisher:
./functions: 44: Syntax error: "(" unexpected

So I went into functions line 44 and this is what's there:

function message_status ()

I've been advised that there's not anything wrong with that line, so I'm pretty much stuck...

I don't know if it will make much difference but try running with

sh install.sh

You may need to use sudo. Also make sure you have made it executable with chmod

chmod +x install.sh

If none of this helps then I'd say it's a problem with the install script and you may need to contact the company.

Please check if function message_status () contain a unwanted space

function message_status<space>()

i think it must be

function message_status()

Hope this helps

Did you investigate the energy saving options ? (just a feeling/idea)

I'm afraid I cannot provide a solution but I have the very same problem (but not the same card at all !!!! ).
I cannot tell for how long it's been buggy on my side... But I believe it used to work once (though not quite sure)...

by the way : my laptop fails either when connected to the power and when running on batteries... but... well I don't know... same problem different drivers... what else could it be ? an overflow bug with 64 vs. 32 bits kernels ?

I have an intel PRO/wireless 3945. Here follows some info on my setup (ubuntu 8.04)
I do confirm that the problem most probably occurs after a certain amount of downloads (or uploads, not sure yet) because I realized the problem when I was trying to download a distrib CD : every attempt failed at the same step (23%).

(I'm pretty sure that the remote server was working : I had my iso by using a cable, download all in one attempt).

The wifi LED of my dell laptop turns off when the problem occurs... I can usually get a connexion back by turning the card off then back on (either by software with dellWirelessCtl or by using the keyboard key-mapping (<fn>+F2))... then the green light turns on again and network manager gets an IP... until it RE-Fails again...

Here follows some info I believed to be relevent...

root@roady:~# lspci | grep Network
0c:00.0 Network controller: Intel Corporation PRO/Wireless 3945ABG Network Connection (rev 02)

root@roady:~# lsmod | grep 3945
iwl3945 104820 0
iwlwifi_mac80211 251876 1 iwl3945
led_class 7176 1 iwl3945

root@roady:~# uname -a
Linux roady 2.6.24-19-generic #1 SMP Wed Aug 20 17:53:40 UTC 2008 x86_64 GNU/Linux

Hope it helps... If you want more details, please do not hesitate to ask and tell me where I can look... or how i can debug more stuffs...

Hello!

I had exactly the same problem.

I managed to fix it by reading some forums:
Edit your "install.sh" file, and replace #!/bin/sh by #!/bin/bash

It should work now :)

By the way, I installed the driver and patched the kernel. Now I have an eth0 interface existing, and I can ping web servers.

But I still have no connexion for the rest, for example, konqueror, or even apt-get...

Maybe it's because I'm behind a proxy (My knowledge is really low on network stuff :( ), or there's another trick to do...

Has somebody the solution?

Hello!

I had exactly the same problem.

I managed to fix it by reading some forums:
Edit your "install.sh" file, and replace #!/bin/sh by #!/bin/bash

It should work now :)

By the way, I installed the driver and patched the kernel. Now I have an eth0 interface existing, and I can ping web servers.

But I still have no connexion for the rest, for example, konqueror, or even apt-get...

Maybe it's because I'm behind a proxy (My knowledge is really low on network stuff :( ), or there's another trick to do...

Has somebody the solution?

(oops, truly sorry for double post)

Since installing Ubuntu 9.04 I've had this problem. Everything was fine on 8.10. Changing the install.sh file is going to need some clarification for this newbie. When I do a search, I get 10 possibilities plus a udev-install.sh file. All of the 10 look identical from top to bottom. They are all locked. How do I go about determining which one is the correct one to change? Will I need to unlock to make the change? If so, how do I do that? Thanks.

I also seem to be having this exact same issue, although I'm on 8.10 .