www.zeroshell.org Forum Index www.zeroshell.org
Linux Distribution for server and embedded devices
 
 SearchSearch  RegisterRegister  UsergroupsUsergroups 
 ProfileProfile  Log inLog in  Log in to check your private messagesPrivate Message 

Workaround for Freezing ALIX with WiFi

 
Post new topic   Reply to topic    www.zeroshell.org Forum Index -> Embedded Devices
View previous topic :: View next topic  
Author Message
SysEngBD



Joined: 24 Jan 2011
Posts: 9

PostPosted: Tue Jul 05, 2011 4:17 pm    Post subject: Workaround for Freezing ALIX with WiFi Reply with quote

Hello,

I haven't seen this in the forum, although I have seen references to systems freezing, especially with the madwifi drivers loaded. I as well as some others suspect that the madwifi drivers cause intermittent kernel panics/oops/segfaults. I have a remote WAP running Zeroshell b14 on and ALIX 2d3. It randomly freezes between twice a day and once a week, requiring a hard reboot; an issue not present on some Soekris 5501 boxes without a wireless card. If anyone is having the same issue, a small workaround is to add these two lines to the PreBoot scripts:

echo '30' > /proc/sys/kernel/panic
echo '1' > /proc/sys/kerne/panic_on_oops

The default behavior of Linux (and Zeroshell) is to wait for user input on a kernel panic, and to continue trying to operate after a kernel oops. the above lines instructs the kernel to reboot 30 seconds after a kernel panic, and in the case of an oops, to enact a kernel panic rather than continue trying to operate. Since our ALIX WAP is at a unstaffed remote site, I would prefer it to simply reboot if it runs into a kernel panic.

Basically this has been an adequate solution as the WAP does kernel panic/oops every so often but instead of just stalling, waiting for user input at the terminal, it reboots itself and goes back into operation with users seeing an ~2 minute blip in unavailability. Further, if you don't want the 30 second delay after the panic, you can change the lines to the following (giving a 1 second rather than 30 second delay between panic and reboot):

echo '1' > /proc/sys/kernel/panic
echo '1' > /proc/sys/kerne/panic_on_oops

I hope someone finds this helpful as it's cleared up some headache on my end. (I also have these lines in the main routers just in case but there hasn't been a kernel panic on them and they haven't been rebooted in 5 months).

Cheers
Back to top
View user's profile Send private message
mcmenkes



Joined: 09 Feb 2011
Posts: 2

PostPosted: Wed Aug 31, 2011 8:05 pm    Post subject: Reply with quote

Hi there,

thanks for the info, SysEngBD !

Indeed i have freezes as you described, but i was not sure where they come from.

Now, after reading your post it looks very similiar to my problem.

My specs:
ZS Release 1.0.beta14
[wifi0] Atheros Communications Inc. AR2413 802.11bg NIC (rev 01)
ALIX 2d3

Your workaround is nice and solves the manual reset, but does not the source.

So my question to the forum: Does anybody else have these strange behaviours and how can we fix this permanently ?

After searching around with "freeze" it seems that the problem can be isolated to Wifi / madwifi...i guess Wink

Best regards & thanks in advance

// MCm
Back to top
View user's profile Send private message
mailsvb



Joined: 03 Jul 2009
Posts: 5

PostPosted: Thu Nov 24, 2011 5:14 am    Post subject: Reply with quote

I reported this a while ago...
http://www.zeroshell.net/eng/forum/viewtopic.php?t=1830&start=0&postdays=0&postorder=asc&highlight=

Still not using zeroshell on that ALIX board because of this issue...
Back to top
View user's profile Send private message
maxson



Joined: 12 Oct 2013
Posts: 1

PostPosted: Sat Oct 12, 2013 1:09 pm    Post subject: Reply with quote

i agreed with you my friend Your workaround is nice and solves the manual reset, but does not the source.

free plagiarism checker for teachers online
www.theloop21.com
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    www.zeroshell.org Forum Index -> Embedded Devices All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group