Comments on: Cisco VPN Client freezes system with dual core CPU

By: Jack

Jack — Mon, 25 Jan 2010 09:44:08 +0000

By far this article and the corresponding comments are the best info on this subject on the web. I've suffered with this issue for over a year - and still do unfort.

I've tried EVERYTHING. Can't get OpenVPN or vpnc to work. I get a panic with cisco with wifi or ethernet on a duo core system (Lenovo T60) or on a single cpu Comcrap Presario.

I have upgraded my kernel from 2.6.24.x to 2.6.31.x. Still no luck - though, interestingly enough Mandriva 2010 provides a cisco client with cpu1 shutdown commands built-in. Still doesn't help me though.

I've tried shutting down cpu1 on my Lenovo and I still have the issue. I haven't tried loading cisco before the shutdown nor have I tried the cpu affinitytaskset trick. Sounds promising.

By: computer keeps freezing

computer keeps freezing — Fri, 22 Jan 2010 12:44:53 +0000

i haven't applied this line of command.i'm learning new things from you.thanks

By: Lamnk

Lamnk — Thu, 17 Dec 2009 09:04:42 +0000

Very interesting ! Thanks a lot for mentioning this command. I haven't even heard about it before.

By: Beau

Beau — Thu, 17 Dec 2009 08:02:20 +0000

I've experiencing this freeze problem only when I use vpnclient over a wifi connection, not over a wired connection.

I've been using this solution for a while, after finding it here. I mentioned my problems to a friend of mine and he suggested playing with processor affinity - assigning the vpnclient to a particular CPU.

I've had a pretty good success this evening.

Check out the command
taskset

and assign vpnclient to processor 0
taskset -pc 0 vpnclient connect PCF_file

By: Lamnk

Lamnk — Thu, 17 Dec 2009 01:04:42 +0000

Very interesting ! Thanks a lot for mentioning this command. I haven't even heard about it before.

By: Beau

Beau — Thu, 17 Dec 2009 00:02:20 +0000

By: boynas

boynas — Wed, 04 Nov 2009 00:04:18 +0000

Neither:

sudo echo 0 > /sys/devices/system/cpu/cpu1/online

or

echo 1 | sudo tee /sys/devices/system/cpu/cpu1/online

worked, both gave me permission problems!

Any ideas?

By: boynas

boynas — Tue, 03 Nov 2009 21:24:05 +0000

I am very interested in creating this script. Can you point me in a good direction to learn to do it?

/etc/init.d/vpn_init is a script, so , I could edit it?

Thanks for all your help!

By: Lamnk

Lamnk — Tue, 03 Nov 2009 21:13:03 +0000

Hmm, i'm not sure whether a core should be turn off before or after loading Cisco module. But definitely before connecting.

If a cpu core must be turn off before module loading, you can add the off-command to “start” section in vpnclient_init script, and add on-command to “stop” section.

By: boynas

boynas — Tue, 03 Nov 2009 11:51:18 +0000

This is before loading the kernel module???

This means that loading the module at startup will be stupid since I got kernel panic only while using the Wifi!

I remember I tried this long time ago, but I think that I was disabling the core while the module was loaded just after "vpnclient connect XXXX". Can you confirm this?