[Ibex] ipw3945 roaming is flaky and unstable (regression from feisty fawn)

I've seen something like this on the APs in our popped datacenters. After going back and forth between a couple a few times ipw3945 all of the sudden doesn't let me connect at all and I have to restart the computer (I've figured so far). This laptop is new though, so I didn't know it was okay in previous releases.

For me too for a wpa-enterprise network.

I am assigning this bug to the 'ubuntu-kernel-team' per their bug policy. For future reference you can learn more about their bug policy at https://wiki.ubuntu.com/KernelTeamBugPolicies .

This seems to work lots better now. Using 8.04, fully up to date with -proposed.

Beginning with the Hardy Heron 8.04 development cycle, all open Ubuntu kernel bugs need to be reported against the "linux" kernel package. We are automatically migrating this bug to the new "linux" package. However, development has already began for the upcoming Intrepid Ibex 8.10 release. It would be helpful if you could test the upcoming release and verify if this is still an issue - http://www.ubuntu.com/testing . If the issue still exists, please update this report by changing the Status of the "linux" task from "Incomplete" to "New". We appreciate your patience and understanding as we make this transition. Thanks!

The Ubuntu Kernel Team is planning to move to the 2.6.27 kernel for the upcoming Intrepid Ibex 8.10 release. As a result, the kernel team would appreciate it if you could please test this newer 2.6.27 Ubuntu kernel. There are one of two ways you should be able to test:

1) If you are comfortable installing packages on your own, the linux-image-2.6.27-* package is currently available for you to install and test.

--or--

2) The upcoming Alpha5 for Intrepid Ibex 8.10 will contain this newer 2.6.27 Ubuntu kernel. Alpha5 is set to be released Thursday Sept 4. Please watch http://www.ubuntu.com/testing for Alpha5 to be announced. You should then be able to test via a LiveCD.

Please let us know immediately if this newer 2.6.27 kernel resolves the bug reported here or if the issue remains. More importantly, please open a new bug report for each new bug/regression introduced by the 2.6.27 kernel and tag the bug report with 'linux-2.6.27'. Also, please specifically note if the issue does or does not appear in the 2.6.26 kernel. Thanks again, we really appreicate your help and feedback.

Per a decision made by the Ubuntu Kernel Team, bugs will longer be assigned to the ubuntu-kernel-team in Launchpad as part of the bug triage process. The ubuntu-kernel-team is being unassigned from this bug report. Refer to https://wiki.ubuntu.com/KernelTeamBugPolicies for more information. Thanks.

Just wanted to report that I am on 8.10 (kernel 2.6.27-11-generic) and I am seeing this issue. Just as reported above, at home (two APs, but different SSIDs) things are fine. At work, it roams constantly and often drops stateful connections (e.g.: telnet, RDP, VNC) as a result.

Attached is the system log. I am sure you need something else, so please don't hesitate to ask as this is a major usability issue for me.

Cheers,
Chris

Unfortunately it seems this bug is still an issue. Can you confirm this issue exists with the most recent Jaunty Jackalope 9.04 release - http://www.ubuntu.com/news/ubuntu-9.04-desktop . Please let us know your results. Thanks.

Am 12.05.2009, 22:38 Uhr, schrieb Manoj Iyer <email address hidden>:

> Unfortunately it seems this bug is still an issue. Can you confirm this
> issue exists with the most recent Jaunty Jackalope 9.04 release -
> http://www.ubuntu.com/news/ubuntu-9.04-desktop . Please let us know
> your results. Thanks.

Dear Manoj,

I've worked around the issue with using alternative WPA offerings that
have appeared in the meanwhile (there are other bugs though that I've
reported separately - network-manager, for instance), and I use
wpa_client, ifplugd, and thereabouts, so retesting is a major undertaking
for me and involves reconfiguring several parts of my system and finding
an environment that still offers WEP.
I cannot set one up myself for lack of suitable access points, so we'll
have to wait until I happen to come across one while travelling.

Since I believe neither in "just try it out" nor "magically self-fixing
bugs": why would anyone assume the bug had disappeared in the next
releases? Is there evidence in the driver's or wpa_applicant's changelogs
that the bugs might have been fixed, and what its nature was?

I don't mean to complain, but this is really a reason to deal with bugs
promptly, rather than defer to upstream or whoever, and wait for somebody
else to fix them. We're now 20 months and three releases past the
report...

Sorry.

--
Matthias Andree

Hello,

Similar to Matthias, I have worked around this by removing Network Manager and installing Wicd instead. The benefit that Wicd gives is that you can specify which AP to latch on to. This has completely eliminated this issue for me. Here's why:

Through a combo of system logs and Wireshark, what I determined is that intermittently when it roams, it is unable to reconfirm its DHCP lease for some reason. This causes the IP to be unbound from the interface, thus dropping all connections. Sometimes it would renew the lease on its own, but sometimes I had to stop and restart Wireless via Network Manager in order to get it to do so.

So, by using Wicd to specify one - and only one - AP for it to use when I am in various places in the building, it prevents the issue above from happening.

On the downside, I did get kernel-panics when making changes in Wicd while connected to an 802.11g AP at home (which I am no longer using). Can't say what caused, that, though. Just trying to be even-handed here.

Specific to this bug, in my research on the Intertoobz it seems that either the 3945 hardware itself or the drivers themselves is far too aggressive when it comes to roaming. This is why the issue only occurs for folks in an Enterprise environment (e.g.: multiple APs all with the same SSID). Home users who have only one AP would not see this issue.

Another important note: I had this issue on the same laptop back when it was running Windows XP. Changing the roaming aggressiveness and power in the Windows driver config had no perceivable affect on the symptom. Other Windows users with the same chipset also had the same issue.

So, unless there is an issue in the driver (as opposed to the hardware), I am not sure what progress can be made on this.

As always, YMMV and what I wrote above should be taken with a metric ton of salt.

Cheers,
CJC

Hi Mathias,

Lets try to gather some more current debug information about this bug if possible. I believe one of the reasons Manoj wanted you know if you, the original bug reporter, saw this against Jaunty is that this bug was originally reported agains the ipw3945 driver. This driver has since been deprecated in favor of the newer iwl3945 driver. Not having heard back from you it probably wasn't clear if this newer driver had resolved the issue you were seeing. Even if it did not resolve the issue, we want to gather debug information ran against the latest driver/source available.

That being said, it would be really great if you could confirm this issue exists with the actively developed Karmic 9.10 Alpha development release of Ubuntu. ISO CD images are available from http://cdimage.ubuntu.com/releases/ . If the issue remains, please then run following command from a Terminal (Applications->Accessories->Terminal). It will automatically gather and attach updated debug information to this report.

apport-collect -p linux 147439

Thanks in advance.

This bug report was marked as Incomplete and has not had any updated comments for quite some time. As a result this bug is being closed. Please reopen if this is still an issue in the current Ubuntu release http://www.ubuntu.com/getubuntu/download . Also, please be sure to provide any requested information that may have been missing. To reopen the bug, click on the current status under the Status column and change the status back to "New". Thanks.

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