FFS_ROOT is gone?

Harald Schmalzbauer h at schmalzbauer.de
Tue Jul 15 16:48:32 PDT 2003

Bernd Walter wrote:
> On Tue, Jul 15, 2003 at 12:22:31PM -0700, Tim Kientzle wrote:
> > Harald Schmalzbauer wrote:
> > >The problem is solved. It was stupid, but I thought why should
> I have to
> > >set
> > >/ in /etc/fstab when the filesystem isn't mounted yet, so the
> file can't be
> > >read.
> > >But it seems the kernel reads this file "loader-like" *before* the
> > >filesystem is mounted.
> >
> > I believe that the loader actually reads this file (it
> > has to be able to locate and read files from UFS anyway
> > in order to load the kernel) and passes the root f/s
> > information to the kernel when it boots.  This should
> > probably be documented in fstab(5)
> You can pass a filesystem at the loader prompt:
> vfs.root.mountfrom=""
> > >Considering the above to be correct I can't understand the
> ability to enter
> > >e. g. ufs:/dev/ad0a at "mountroot>" when it doesn't work.
> >
> > I've also been stung by the fact that the
> > "mountroot>" prompt is broken.  <sigh>
> > I looked briefly at the code, but the
> > bug is not particularly obvious.
> At least it wasn't broken a while ago.
> What happens exactly after entering the correct device?

The machine rebooted. No matter if I did "?" or any "ufs:xxYz". It's
behaviour was like "empty line".

That was mine dunno about Tim's

Regarding loader reades /etc/fstab: Of course loader and even boot can read
from ufs but I verified that current device was disk0s1 (where my 165-ID
was) and also something like root-mount was set to disk0s1.

Next thing is that boot0 could'nt boot my kernel (5.1-release).
Some time ago I built a little accesspoint with 4.6 and there was no problem
booting the kernel with only boot0, no loader.

Has this feature been intentionally removed?

Best regards,


> --
> B.Walter                   BWCT                http://www.bwct.de
> ticso at bwct.de                                  info at bwct.de

More information about the freebsd-current mailing list