Date: Tue, 14 Mar 2006 12:16:23 -0500
From: Gene Heskett <gene.heskett@verizon.net>
Subject: Re: Dmesg is not showing whole boot list
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On Tuesday 14 March 2006 10:05, Phillip Susi wrote:
>Or look in your /var/log/kern.log file instead of asking dmesg.  dmesg
>just dumps the kernel ring buffer which is of finite size.  The entire
>contents should be logged to /var/log/kern.log.

You've got to have /var checked and mounted to be able to do that log 
write, if the buffer overflows before that, then the head end of the 
dmesg dump to the /var/log/dmesg file is lost forever.

There is a line that can be changed, in xconfig or by hand, to control 
the memory allocated for this ring buffer.

Finally found it in the xconfig display, left panel line=kernel hacking, 
right panel its under kernel debugging and shows only if thats checked, 
double click on the line that says : kernel log buffer size and enter a 
one digit increment from whats there now, maybe 2, I have mine set for 
16.  Your default may be as low as 14, why I have NDI because 16k sure 
as heck isn't enough if something gets chatty.

>Peter Hagervall wrote:
>> On Tue, Mar 14, 2006 at 09:01:27AM +0100, CIJOML wrote:
>>> Hello,
>>>
>>> maybe this si a wrong list to ask, bug after boot, dmesg shows that
>>> few lines at the beginning are missing.
>>>
>>> Is there any option I can increase to get full dmesg?
>>
>> Try increasing CONFIG_LOG_BUF_SHIFT and recompile. That's likely the
>> source of your problem.
>>
>>
>>
>> 	Peter Hagervall
>
>-
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-- 
Cheers, Gene
People having trouble with vz bouncing email to me should add the word
'online' between the 'verizon', and the dot which bypasses vz's
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