KernelPanic

Category:Sasecurity
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=== roboot on kernal panic ===
Isn't this the same as the one that Don says won't work? Or does it only work uner some circumstances?
> #!/bin/sh
> #
> # /etc/rc.d/rc.local: Local system initialization script.
> #
> # entry to reboot 30 secs after a kernel panic
> echo 30 > /proc/sys/kernel/panic
> This is what I put in my rc.local on the mesh box here.
> To make it work you would need to reboot the mesh box.
> But you can make it work without rebooting by using :-
>echo 30 > /proc/sys/kernel/panic from a root login to mesh box. I had problems here occasionally with kernel panics and since implementing > this solution, the box now reboots and comes up cleanly after a kernel > panic.
Putting the above in rc.local means the box will always reboot on a kernel panic.
>>Yeah this doesn't work. Tried it a number of times and when a kernel
>>panics, it's too late. Sorry I didn't report on this sooner.
This might help you guys If you experience occasional kernel panics (machine freezes,
>>> keyboard LED's, if attached, blink) try the following:
>>> Edit the normally empty file /proc/sys/kernel/panic to add the
>>> number "30" (without the quote marks). This will the reset the node
>>> 30 seconds after a kernel panic.
>>> (copied from the qorvus bbs)
>>> I looked in the wiki and also searched thru my emails and 
couldnt
>>> find anything on making a mesh ap recover from a kernal panic.. 
but
>>> I thought I had read about how to do it but dang if i can find 
it.. 
>>> is the
>>> the internal watchdog setting in wiana, if it is all mine are on 
yes
>>> and always have been. i have some messages from kenny and you
>>> on using a pager for reset which is NOT an option for me right 
now..
>>> btw since i have reduced the size of my mesh.. i have went about 
6
>>> weeks without anything really going crazy... almost all the 
nodes i
>>> have now are on car batteries(at the wrap boards) and UPS on the
>>> mini itx nodes. I have one pcengines wrap board runnin dev 76 
that
>>> is on a car battery and has not required a power reset in almost 
5
>>> months. The car battery is actually about 3 feet from the node 
and
>>> is on top of a water tower. I just use a regular 12 volt 1 amp 
power
>>> supply at the bottom of the tower to feed the battery and node. 
Just
>>> thought I would throw that in there for someone who might still 
be
>>> using wrap boards. One thing I have learned is the wrap boards 
will
>>> work on any voltage in their range... BUT they DO NOT HAVE
>>> enough filter on their power input. VERY large filter 
capacitors(4000
>>> ufd or larger) RIGHT at the power plug solves a lot of issues 
and a
>>> battery is even better.
>>> The graphs are really kewl but right now way over my head
>>> technically to implement
>>> It may be hard, but don’t give up. Just work with what you
>>> have. My piece of advice is to go with Qcode. Since we have gone
>>> with Qcode, our crashes have almost stopped, and our total
>>> throughput and pingtime are much lower. We had major problems
>>> before with nodes crashing ever day clients just hating us. One 
of
>>> the big problems, which is actualy pretty simple, was to have 
the
>>> node reboot if it hit a kernal panic. Now instead of the whole 
>>> network
>>> going down, it just has a few mintues of rebooting. Then since I
>>> track our reboots I can go out and deal with the hardware issues 
on
>>> my time, not in an emergency state.
>>> Another thing to do to really 'see' your mesh is to graph graph
>>> graph.. I have the mehspoints FTPing much info which I parse and
>>> then insert into an RRD database. Here is some of my graphs.
=== Use a pager ===
Bob this too is excellent; unfortunately, we cannot recompile the kernel!
Take a look at: http://www.faqs.org/docs/Linux-HOWTO/Linux-Crash-HOWTO.html
It has a small C program that calls panic() to force a panic.
If you experience occasional kernel panics (machine freezes, keyboard LED's, if attached, blink) try the following Edit the normally empty file /proc/sys/kernel/panic to add the number "30" (without the quote marks). This will the reset the node 30 seconds after a kernel panic. We all have crashes.. but nobody likes to talk about it. We have created a pager reset to deal with the >
Category:Mesh