Gaining access to disks made inaccessible
Peter K. Hadley
phadley at village.com
Thu Jul 21 16:39:25 GMT 2005
I have made my machine unbootable. I installed FreeBSD on ad0s2, a
partition of one physical hard drive. I put most of my working data on
ad1s2, a partition of another much larger hard drive. I then created
links from /home, /etc, and /usr to the second drive. This worked well
until the power outages. The second drive was always sufficiently well
corrupted that it refused to be mounted. Because fstab failed, booting
quit. This was cured by fsck but I was hoping to run the machine
headless as good discipline for a real server so I had to grab the
keyboard from another machine in a geometrically compromised setting and
To forestall this problem, I edited fstab to make the second disk
noauto. At the very next power outage, it started booting and did quite
well at it until it tried to grab a terminal from /usr. This was linked
to the now unmounted disk. I had no obvious way of getting a command
prompt to mount the disk. I stumbled on the Fixit disk and it was fun
but after fsck it could find only lost+found on the drive and never
could mount the first drive (bad superblock). I couldn't even fsck it.
Is there some way to get at either /etc/fstab or to rearrange all those
links so that I can get everything? All I want is access to / on the
first disk. From there I should be able to rearrange things so the
machine is usable and then I can mess it up in a new way.
I think in the future, I'll have /usr in the directory where I mount the
second drive. That way it will be there until I place the new one over
it. If that doesn't work, I think I'll just have only /home on the
second drive and live with it.
Thank-you for listening and I thank you for any advice, especially
advice that works.
More information about the freebsd-questions