[GLLUG] Using network-manager to access wireless nodes on MSU campus

[Brent W. Barker]

Hi all,

I'm running Ubuntu 11.10 and 12.04, and having trouble staying connected 
to the wireless network at MSU. I think it has to do with multiple 
access points being assigned to the same ESSID. Is anyone else having 
this problem? Here's a summary from my blog post on the matter:


About a month ago, I started having problems connecting my Ubuntu 11.10 
laptop to MSU’s wireless network. In the morning, when I would connect, 
it would do so successfully for 10 minutes to an hour. Then it would 
stop working, and just try to repeatedly connect. I don’t know where to 
file this bug under, so for now, I’ll just store the info on my blog.

For example, here’s a section of /var/log/syslog from today:

Mar 21 11:36:20 friday wpa_supplicant[1441]: Trying to authenticate with 
00:0c:e6:6d:9a:7f (SSID='MSUnet 2.0' freq=5180 MHz)

Mar 21 11:36:20 friday kernel: [231715.216575] wlan0: direct probe to 
00:0c:e6:6d:9a:7f (try 1/3)

Mar 21 11:36:20 friday kernel: [231715.416174] wlan0: direct probe to 
00:0c:e6:6d:9a:7f (try 2/3)

Mar 21 11:36:20 friday kernel: [231715.616246] wlan0: direct probe to 
00:0c:e6:6d:9a:7f (try 3/3)

Mar 21 11:36:21 friday kernel: [231715.816115] wlan0: direct probe to 
00:0c:e6:6d:9a:7f timed out

Mar 21 11:36:28 friday wpa_supplicant[1441]: Trying to authenticate with 
00:0c:e6:6d:9a:7f (SSID='MSUnet 2.0' freq=5180 MHz)

Mar 21 11:36:28 friday kernel: [231723.286531] wlan0: direct probe to 
00:0c:e6:6d:9a:7f (try 1/3)

Mar 21 11:36:28 friday kernel: [231723.484108] wlan0: direct probe to 
00:0c:e6:6d:9a:7f (try 2/3)

Mar 21 11:36:28 friday kernel: [231723.684256] wlan0: direct probe to 
00:0c:e6:6d:9a:7f (try 3/3)

Notice that the timeout seems to be about 200 milliseconds. Not very 
long. Watching the output of wpa_cli, I saw it add and remove APs from 
its list at an alarming rate. Indeed, it was adding and removing them as 
fast as it was timing out. At my university, there are multiple Access 
Points (APs) for every SSID, and I think it was getting hung up on it.

So, after scouring the net for help and not getting much, I did 
eventually find someone advising to run wpa_supplicant myself, without 
using network-manager, which is what Ubuntu currently uses to manage 
wpa_supplicant. Given that this is how I used to manage my network 
connections when I ran Gentoo, I decided to give it a try.

So, I stopped network-manager with a ‘sudo /etc/init.d/network-manager 
stop’ command, and killed the wpa_supplicant process that was still 
running. I created my own wpa_supplicant configuration file, in 
~/sandbox/wpasup.conf:

network={ ssid="MSUnet 2.0" scan_ssid=1 key_mgmt=NONE }

network={ ssid="MSUnet Guest 2.0" scan_ssid=1 key_mgmt=NONE }

After saving this file, I just needed to run my own process of 
wpa_supplicant, then once it connected to the AP, run dhclient to have 
DHCP give me an IP and all that.

$ sudo wpa_supplicant -iwlan0 -s -d -c/home/user/sandbox/wpasup.conf 
/var/run/wpasupplicant

$ sudo dhclient wlan0


Thanks,
Brent