Intel 4965 wireless can't see wifi channels 12 and 13

[Thomas Dahlmann]

When I upgraded my laptop to Intrepid alpha 6, from Hardy, I couldn't connect to my WPA2 enabled wireless. When doing scans it could only see open or WEP protected networks.

I tried to downgrade wpasupplicant to the same version in Hardy but with same result. I tried using Wicd instead of NM but didn't do any difference. I also tried using wpagui and wpa_supplicant on the commandline, no success.

There is nothing wrong with the AP as I can connect from the same machine when I inject a D-Link DWL-AG650 pc-card (using the atheros driver).

I suspect it is the either kernel or iwl-driver related.

[edit: see comments below for clarification that the problem seems to be related to AP channel number]

[Thomas Dahlmann (dahlmann)]

The nic is a Intel 4965AGN

[Thomas Dahlmann (dahlmann)]

Still an issue with latest kernel update (2.6.27-5-generic #1 SMP Fri Oct 3 00:38:23 UTC 2008 i686 GNU/Linux)

 sudo iwlist scan
[sudo] password for tdd:
lo Interface doesn't support scanning.

eth0 Interface doesn't support scanning.

wmaster0 Interface doesn't support scanning.

wlan0 Scan completed :
          Cell 01 - Address: 00:13:49:52:4D:06
                    ESSID:"MattssonNet"
                    Mode:Master
                    Channel:6
                    Frequency:2.437 GHz (Channel 6)
                    Quality=38/100 Signal level:-86 dBm Noise level=-127 dBm
                    Encryption key:on
                    IE: WPA Version 1
                        Group Cipher : TKIP
                        Pairwise Ciphers (1) : TKIP
                        Authentication Suites (1) : PSK
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 22 Mb/s
                              6 Mb/s; 9 Mb/s; 12 Mb/s; 18 Mb/s; 24 Mb/s
                              36 Mb/s; 48 Mb/s; 54 Mb/s
                    Extra:tsf=00000004c7326cb8
                    Extra: Last beacon: 4392ms ago
          Cell 02 - Address: 00:1E:8C:62:30:35
                    ESSID:"qzq5yP5u"
                    Mode:Master
                    Channel:6
                    Frequency:2.437 GHz (Channel 6)
                    Quality=35/100 Signal level:-88 dBm Noise level=-127 dBm
                    Encryption key:on
                    IE: WPA Version 1
                        Group Cipher : TKIP
                        Pairwise Ciphers (1) : TKIP
                        Authentication Suites (1) : PSK
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 18 Mb/s
                              24 Mb/s; 36 Mb/s; 54 Mb/s; 6 Mb/s; 9 Mb/s
                              12 Mb/s; 48 Mb/s
                    Extra:tsf=0000008961da1d6a
                    Extra: Last beacon: 4348ms ago
          Cell 03 - Address: 00:1F:C6:E5:47:BC
                    ESSID:"xMRvDhNy"
                    Mode:Master
                    Channel:11
                    Frequency:2.462 GHz (Channel 11)
                    Quality=28/100 Signal level:-92 dBm Noise level=-127 dBm
                    Encryption key:on
                    IE: WPA Version 1
                        Group Cipher : TKIP
                        Pairwise Ciphers (1) : TKIP
                        Authentication Suites (1) : PSK
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 18 Mb/s
                              24 Mb/s; 36 Mb/s; 54 Mb/s; 6 Mb/s; 9 Mb/s
                              12 Mb/s; 48 Mb/s
                    Extra:tsf=000001151a962183
                    Extra: Last beacon: 576ms ago

wifi0 Interface doesn't support scanning.

ath0 Scan completed :
          Cell 01 - Address: 00:1E:8C:62:30:35
                    ESSID:"qzq5yP5u"
                    Mode:Master
                    Frequency:2.437 GHz (Channel 6)
                    Quality=7/70 Signal level=-88 dBm Noise level=-95 dBm
                    Encryption key:on
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 18 Mb/s
                              24 Mb/s; 36 Mb/s; ...

[ThomasDahlmann (tdd-lnxgeek)]

It seems that the driver only finds AP's using channel 1-11. Changing the AP to within this range it finds it and network is working again.

I was fooled by the atheros and iwl3945 drivers ability to see and use channel 12 and 13.

[Dave Nice (dave-niceweb)]

Hi,

I also had this problem - my AP was on channel 13 and intrepid couldn't see it at all. Hardy had been able to see it but struggled to connect.

I guess this is a difference in the iwlagn driver compared to iwl4965?

Is there any useful debug I can provide for this problem?

Dave

[Dave Nice (dave-niceweb)]

Aha - looking at bug 275279 and adding this line to my /etc/modprobe.d/options
options cfg80211 ieee80211_regdom="EU"

"iwlist wlan0 channel" now reports seeing channels 12 and 13. Will check it has worked when I get home.

[Miguel Martinez (el-quark)]

I want to confirm this behaviour in the Intel WiFi Link 5300 present on my Thinkpad T400. Dave Nice's advice worked great, and only putting off and on again iwlagn was enough to detect my AP.

[Linuxluver (sbwithers)]

Dave's comment above fixed my problem. I have an Acer 2483 TravelMate laptop with an Atheros wireless chipset.

Before I added the "options" line above to /etc/modprobe.d/options (and re-booted), my wifi only saw 11 channels. But now it sees 13.

steve@steve-laptop:~$ iwlist wlan0 channel
wlan0 13 channels in total; available frequencies :
          Channel 01 : 2.412 GHz
          Channel 02 : 2.417 GHz
          Channel 03 : 2.422 GHz
          Channel 04 : 2.427 GHz
          Channel 05 : 2.432 GHz
          Channel 06 : 2.437 GHz
          Channel 07 : 2.442 GHz
          Channel 08 : 2.447 GHz
          Channel 09 : 2.452 GHz
          Channel 10 : 2.457 GHz
          Channel 11 : 2.462 GHz
          Channel 12 : 2.467 GHz
          Channel 13 : 2.472 GHz
          Current Frequency=2.472 GHz (Channel 13)

My AP is on Channel 13 and was not visible prior to this change. Now, I can connect to the same AP with no problems (D-Link DI-624S set to "auto" with respect to channels).

[ugm6hr (ugm6hr)]

This is a known "bug" for European and Japanese users:
http://www.ubuntu.com/getubuntu/releasenotes/810#Only%20US%20wireless%20channels%20enabled%20by%20default%20on%20Intel%203945

[Linuxluver (sbwithers)]

...and users in Australia and New Zealand.

These days, for global standards, "European" means pretty much everyone
outside North America. The US tends to do its own thing and everyone else
does the OTHER thing. In the case of frequencies, the US reserved many
frequencies for military use that are open frequencies everywhere else. This
is why North American cell phones were for years different to everyone
else's cell phones.

Steve Withers
<email address hidden>
[phone]
(voice, txt or video)

On Sun, Mar 8, 2009 at 1:44 AM, ugm6hr <email address hidden> wrote:

> This is a known "bug" for European and Japanese users:
>
> http://www.ubuntu.com/getubuntu/releasenotes/810#Only%20US%20wireless%20channels%20enabled%20by%20default%20on%20Intel%203945
>
> --
> Intel 4965 wireless can't see wifi channels 12 and 13
> https://bugs.launchpad.net/bugs/275279
> You received this bug notification because you are a direct subscriber
> of the bug.
>

[Miguel Martinez (el-quark)]

I'd like to make a small point. If you are using linux-backports-modules (lbm) because you need a newer wifi driver, the module that regulates which channels you see is no longer "cfg80211" but "lbm_cw_cfg80211". Thus, the line that needs to be added to /etc/modprobe.d/options is

options lbm_cw_cfg80211 ieee80211_regdom="EU"

Unloading and reloading the wifi modules works like a charm, no need to reboot.

By the way, is it a bug that linux-backports-modules doesn't detect the options appended in /etc/modprobe.d/options and modifies it for the modules included in that package? I mean, because some slightly differently named modules are used, I'd expect them to pick the options applied to the original ones.

[Andy Whitcroft (apw)]

This is a limitation of the regulatory handling in the kernel. For intrepid the you will need to use the module option work around:

    options cfg80211 ieee80211_regdom=<country code>

For Jaunty and later the new crda regulatory domain daemon in combination to the passive scanning support should trigger these channels automatically when a beacon is seen.

Closing Won't FIx for Intrepid and Fix Released for Jaunty and later.