Unable to boot FreeBSD 8.0-p3

[Jeremy Chadwick]

On Thu, Jul 01, 2010 at 11:59:43PM +0800, GNUbie wrote:
> Hello MV,
> 
> On Thu, Jul 1, 2010 at 11:47 PM, M. Vale <maurovale at gmail.com> wrote:
> >
> > Hum strange I've seen this occur on 2 types of situations:
> >
> > 1 - virtualbox or other module loaded at boot time
> > 2 - Hardware problem
> >
> > To fix it you have a list of small options.
> >
> > The first one is by booting with the FreeBSD CD and choosing rescue/upgrade
> > system
> >
> > Other option is by removing Memory DIMM's to ensure that the problem is not
> > caused by a fault RAM module.
> 
> I am currently running memtest86 here on my livecd. If there is no
> error, then this could be something else.
> 
> Still strange for me on the stdout before my system reboots that says:
> "Cannot dump. Device not defined or unavailable." Does it mean that
> when loading the kernel, it cannot dump it to the / or some other
> designated place?

Kernel crash dumps are not enabled by default.  You need to define the
following in /etc/rc.conf before that will happen:

dumpdev="auto"

Be aware that kernel crash dumps don't always work reliably -- or
rather, the savecore(8) portion (once the system is back up, writing the
crash details to files in /var/crash on the filesystem).  Of course, I'm
going off of history (circa 2007), but there wasn't ever any indication
that the problem was fixed:

http://www.freebsd.org/cgi/query-pr.cgi?pr=118255

If you can't get the OS installed (e.g. this is happening when booting
the FreeBSD installation CD), you're kinda out of luck, unless others
know of a way around it.

-- 
| Jeremy Chadwick                                   jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                  Mountain View, CA, USA |
| Making life hard for others since 1977.              PGP: 4BD6C0CB |