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oliwel
December 17th, 2008, 04:20 AM
Hi Folks,

I am running ibex on a Thinkpad X 300 using iwlagn driver for the builtin card. At home, with a WEP secured network, I never saw problems.

Now, I am on a vacation and tried to connect to the offered unsecured WLAN - it worked without problems BUT after I connect, I am unable to run DNS queries.

Summary:

NetworkManager found SSID and connects
System seems to work
After approx. 10 Seconds, I am unable to reach the DNS Server anymore
Issueing a reconnect, brings back DNS for about 10 Seconds


Here is what I tracked down:

The daemon.log


Dec 17 04:03:30 aurum NetworkManager: <info> DHCP: device wlan0 state changed preinit -> bound
Dec 17 04:03:30 aurum NetworkManager: <info> Activation (wlan0) Stage 4 of 5 (IP Configure Get) scheduled...
Dec 17 04:03:30 aurum NetworkManager: <info> Activation (wlan0) Stage 4 of 5 (IP Configure Get) started...
Dec 17 04:03:30 aurum NetworkManager: <info> address 172.22.220.69
Dec 17 04:03:30 aurum NetworkManager: <info> prefix 24 (255.255.255.0)
Dec 17 04:03:30 aurum NetworkManager: <info> gateway 172.22.220.1
Dec 17 04:03:30 aurum NetworkManager: <info> nameserver '192.168.1.1'
Dec 17 04:03:30 aurum NetworkManager: <info> domain name 'nomadix.com'
Dec 17 04:03:30 aurum NetworkManager: <info> Activation (wlan0) Stage 5 of 5 (IP Configure Commit) scheduled...
Dec 17 04:03:30 aurum NetworkManager: <info> Activation (wlan0) Stage 4 of 5 (IP Configure Get) complete.
Dec 17 04:03:30 aurum NetworkManager: <info> Activation (wlan0) Stage 5 of 5 (IP Configure Commit) started...
Dec 17 04:03:31 aurum NetworkManager: <info> (wlan0): device state change: 7 -> 8
Dec 17 04:03:31 aurum NetworkManager: <info> Policy set 'Sandals' (wlan0) as default for routing and DNS.
Dec 17 04:03:31 aurum NetworkManager: <info> Activation (wlan0) successful, device activated.
Dec 17 04:03:31 aurum NetworkManager: <info> Activation (wlan0) Stage 5 of 5 (IP Configure Commit) complete.
Dec 17 04:03:53 aurum NetworkManager: <info> (wlan0): supplicant connection state change: 7 -> 3
Dec 17 04:03:53 aurum NetworkManager: <info> (wlan0): supplicant connection state change: 3 -> 4
Dec 17 04:03:53 aurum NetworkManager: <info> (wlan0): supplicant connection state change: 4 -> 7


Running a loop with a shortlived "dig" command brings results starting around 04:03:38 and ends with the first connection change message at 04:03:53.

Running the wpa-supplicant in debug mode shows, that it starts a rescan after 10 seconds - even as it does not find new access points, it magically crashes the network.

As besides DNS even ntp shows the same behaviour, I guess the whole UDP stack is smashed.

Iptables are empty, when I send the DNS queries through a VPN into my home network, they work!

As I dont have access to the infrastructure, I cannot exclude any missbehaviour at the hotels equipment (they run a "nomadix" access system).

Anybody seen such before? Anybody at hand with a simple solution? I guess preventing a rescan should help.

Oliver

oliwel
December 18th, 2008, 02:40 AM
Some additional Info - above applies to a fully patched ibex system as of Dec 5.
When I boot into an older kernel (2.6.24), the system uses another drover iwl4965 and it works!
So it seems to be an issue with the driver.

Oliver