what should uname -v be telling me here?

Polytropon freebsd at edvax.de
Fri Jun 27 21:04:57 UTC 2014


On Fri, 27 Jun 2014 13:57:06 -0700, paul beard wrote:
> On Fri, Jun 27, 2014 at 1:36 PM, Polytropon <freebsd at edvax.de> wrote:
> > You need to find out where /boot resides (in my case,
> > it's on ad4s1a, which is mounted at /) to identify the boot
> > device (or to be precise, the device the kernel has been read
> > from).
> 
> 
> I keep thinking this should be something you ought to be able to
> discover without being on console. I realize the BIOS can't be
> interrogated but if I knew that the active kernel was ad3:/boot/kernel
> or ad2:/boot/kernel, it would be useful. Kind of surprised that
> doesn't appear anywhere in dmesg or that it can't be read out of
> somewhere.

There is an entry in /var/log/messages and dmesg:

	% dmesg | grep "mount root"
	Trying to mount root from ufs:/dev/ad4s1a

But as I said, this is where the root file system has been
mounted from. It doesn't _have to be_ the same file system
the kernel has been read from (or where the system has been
booted from).

It's possible to construct a boot chain where the BIOS starts
booting from ad2, which reads the kernel from a partition
on ad4, and which continues to mount root from ad6 (which
is called ada0). Those disks could be identified as disk0,
disk1 and disk2 to the BIOS...




-- 
Polytropon
Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...


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