Today I upgraded my development server from FreeBSD 7.2 to FreeBSD 8.0-PRERELEASE.
I had recently upgraded from 6.4 to 7.2, so I expected no problems upgrading
to 8.0, as supported by recent experiences with a few other machines.
I was wrong. When rebooting the 8.0 kernel, the system could not find
/dev/mirror/gm0s1c. All it saw was:
[dan@ngaio:~] $ ls -l /dev/mirror/
crw-r----- 1 root operator 0, 100 Nov 18 23:29 gm0
crw-r----- 1 root operator 0, 103 Nov 18 23:29 gm0s1
I altered /etc/fstab to comment out that line and proceeded to boot. That
worked. That partition c is no longer present. c was always a "magic"
partition in that it existed even without a disklabel and encompassed
the entire slice. I altered my /etc/fstab as shown and the mount now
< /dev/mirror/gm0s1c /wdc ufs rw 2 2
> /dev/mirror/gm0s1 /wdc ufs rw 2 2
That fixed it.