[ltp] iwl4965, Hardy x86_64, and frustration (long)

[Micha]

On Wed, 7 May 2008 22:13:37 -0700
John Jason Jordan <johnxj@comcast.net> wrote:

> I have had  my T61 with nVidia and 4965agn wireless for over a year. In
> all that time I have run only Ubuntu x86_64.=20
>=20
> Some additional facts:
> At home my house is wired for ethernet and I have a cable connection,
> so wireless is not only not needed, there is no wireless network to
> connect to. Having said that, the neighbors have wireless and their
> networks are visible, even if they are secured so I can't connect to
> them. In order to test wireless I have to go to the university, a
> coffee shop, or some other location. Unless I make a special trip, this
> happens two-three times a week.
>=20
> The problem:
> Right from the beginning (Feisty, x86_64 through Gutsy x86_64) the
> 4965agn did not work well. I could connect, but I would get disconnects
> (random, not timed). The weaker the signal the faster the disconnect. I
> could not tell that I was disconnected until suddenly I could not go
> anywhere. Network Manager would always say I was connected and would
> show the IP address for DHCP. Ditto for Wifi-Radar. After much research
> I figured out that I was still connected to the access point, but had
> lost my DHCP lease. Yet the command line and the GUIs insisted that I
> was connected and had an IP address.
>=20

For me it shows that it is disconnected. I found that with wpa it is worse =
then
others and usually if there is load on the network it works better. I
attributed the problem to power management.

As for unloading the driver, I found that it works well (only thing that wo=
rks
for me), but you need to wait a few seconds between unloading and reloading=
 the
driver for the hardware to settle down. If I reload it too fast it doesn't =
work.

> To fix the problem I used a number of tools. I could kill Network
> Manager and restart it, but this restored the DHCP lease only
> occasionally. Doing "ifconfig wlan0 down" then "up" occasionally
> restored the connection, although not usually.
> "Sudo /etc/init.d/networking restart" would sometimes get me going
> again, but usually not. "Modprobe -r iwl4965," followed by reinserting
> it, would also occasionally work. If I poked at the problem repeatedly
> with these tools I could restore the connection most of the time, but
> not always.
>=20
> System > Administration > Network showed the wireless connection. It
> was set by default to roaming mode. (Side comment: I have searched all
> the Ubuntu forums without finding a definition of what the hell
> "roaming mode" means. It must mean my cell phone company will charge me
> extra for time connected via wireless, but that doesn't make sense.)
>=20
> If i change the wireless connection from roaming mode I have to enter a
> network access point and set it to DHCP or something. To do so I need
> to select the wireless device, then click on Properties, then uncheck
> the roaming mode box. It won't accept the new settings until I give it
> an access point. But when I click on the drop-down the available
> networks to connect to appear only about one time out of 20-30 tries.
>=20
> If i use Wifi-Radar it shows all available networks every time.
> However, selecting one and telling Wifi-Radar to connect to it works
> only one out of 5-10 tries. I also installed Kwifimanager, but got more
> or less the same results.
>=20
> Because of the vexation with the 4965agn I borrowed a Netgear WG511T
> PCMCIA card from a friend. It always works just fine.=20
>=20
> Until recently the LED never came on either, whether using the built-in
> 4965 or the Netgear. (See below.)
>=20
> -----------
>=20
> Upgrade to Hardy
>=20
> Last Thursday I upgraded Gutsy x86_64 to Hardy x86_64. Right from the
> beginning there was no difference in the wifi problem. However, I was
> at home and could only poke at Network Manager and Wifi-Radar to see if
> they found any wireless networks. Network Manager and Wifi-Radar saw no
> available networks. And the LED did not come on. That is, until Peter
> Fr=C3=BChberger here told me to install:
>=20
> linux-backports-modules-hardy-generic
> linux-backports-modules-2.6.24-16-generic <- meaning the one matchin to
> your kernel
>=20
> Having followed his advice the LED now comes on. Other problems remain,
> that is, I cannot get a reliable wireless connection.
>=20
> Following advice of others, last night I installed Wicd. Installing
> Wicd automatically uninstalls Network Manager and Wifi-Radar. After
> installing it there seemed to be no change. Wicd could not see any
> wireless networks either. Bear in mind that I was at home where I am on
> ethernet.
>=20
> Today I went to the university. As soon as I was booted up I launched
> Wicd. And lo and behold, it displayed all available networks.
> (Evidently it failed to do so at home because I was already connected
> at the time via ethernet.) I selected the student network
> (pubnet.pdx.edu) and a few moments later I was connected with an IP
> address. I was happily able to go anywhere on the net. And about an
> hour later suddenly I wasn't going anywhere again. Lost the DHCP lease.
> Same problem as before. At the time I was sitting directly under an
> access point.
>=20
> Meantime, I hear form a number of people who say have the 4965agn card
> working fine. In all cases so far, they are using a different distro, a
> 32-bit architecture, or are really running a 3945 instead of a 4965, or
> something else significant is different.
>=20
> I have googled and found a number of posts about the random
> disconnects. All are over a year old. None say what they did to fix the
> problem, or if their fix involved throwing the T61 in the river and
> buying a different laptop.
>=20
> ------------
>=20
> Suggestions needed:
> I would be happy to post back the response from any command line
> commands if such would help people diagnose the problem. I am not
> extremely knowledgeable about networking, but can follow detailed
> instructions faithfully.
>=20
> If someone has the 4965agn working without a problem in 64-but Hardy, I
> would appreciate any insights you can offer.
>=20