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To: Paolo Pisati <p.pisati@oltrelinux.com>
In-Reply-To: Your message of "Wed, 04 Jun 2003 12:04:03 +0200."
             <20030604100403.GA1273@southcross.skynet.org> 
Date: Thu, 05 Jun 2003 11:15:01 +0100
From: Ian Dowse <iedowse@maths.tcd.ie>
Message-ID: <200306051115.aa28978@salmon.maths.tcd.ie>
cc: FreeBSD_Current <freebsd-current@FreeBSD.ORG>
Subject: Re: msgbuf cksum mismatch (read 933e3, calc 93fbe) 
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In message <20030604100403.GA1273@southcross.skynet.org>, Paolo Pisati writes:
>
>What does it mean?
>
>It's the first row in my today's kernel.

You can safely ignore it. Some BIOSes don't clear the RAM during a
reboot, so when booting up, FreeBSD attempts to pick up the kernel
message buffer from before the reboot (this can be very handy if
the reboot was caused by a panic). The above message indicates that
the message buffer from the last boot initially appeared to be
intact, but its checksum didn't match the contents, so it was
cleared.

I guess the message could be changed to cause less alarm, or it
could be hidden behind bootverbose; I just thought it useful to
indicate that the previous message buffer was mostly there in case
somebody who really needs it preserved wants to disable the check.
The behaviour here could possibly also be made a loader.conf tunable,
but I didn't test whether tunables can be used that early in the
boot process.

Ian