fsck: CANNOT SEEK BLK: -1 (Cannot find file system superblock)

[itetcu at tecnik93.com]

[Please cc and excuse the formating as I'm forced to use the webmail 
for now]

Hi,


I've changed, as a result of a failure, my mobo from a GA-7VT600 1393 
to a GA-7VT600-L, both with VIA Apollo KT600 / 8237 cipset. The system 
is FreeBSD5.1 Release with a Seagate ATA Baracuda V 120G HDD. (Of 
course, the Xp boots up with no problem.)
The / was mounted read-only.

When I try to boot I get:
/dev/ad0s2a: FILESYSTEM CLEAN; SKIPPING CHECKS
/dev/ad0s2a: clean, 89827 free (715 frags, 11139 blocks, 0.6% 
fragmentation)
Cannot find file system superblock
/dev/ad0s2e: CAN'T CHECK FILE SYSTEM.
/dev/ad0s2e: UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY.
/dev/ad0s2e: CANNOT SEEK BLK: -1
/dev/ad0s2e: UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY.
Cannot find file system superblock
/dev/ad0s2f: CAN'T CHECK FILE SYSTEM.
/dev/ad0s2f: UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY.
/dev/ad0s2f: CANNOT SEEK BLK: -1
/dev/ad0s2f: UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY.
Cannot find file system superblock
/dev/ad0s2d: CAN'T CHECK FILE SYSTEM.
/dev/ad0s2d: UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY.
Cannot find file system superblock
/dev/ad0s2g: CAN'T CHECK FILE SYSTEM.
/dev/ad0s2g: UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY.
/dev/ad0s2g: CANNOT SEEK BLK: -1
/dev/ad0s2g: UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY.

A fsck -t ufs ad0s2d gives:
** /dev/ad0s2d
Cannot find file system superblock
/dev/ad0s2d: INCOMPLETE LABEL: type 4.2BSD fsize 0, frag 0, cpg 0, 
size 1048576



******* Working on device /dev/ad0 *******
parameters extracted from in-core disklabel are:
cylinders=232578 heads=16 sectors/track=63 (1008 blks/cyl)

Figures below won't work with BIOS for partitions not in cyl 1
parameters to be used for BIOS calculations are:
cylinders=232578 heads=16 sectors/track=63 (1008 blks/cyl)

Media sector size is 512
Warning: BIOS sector numbering starts with sector 1
Information from DOS bootblock is:
The data for partition 1 is:
sysid 12 (0x0c),(DOS or Windows 95 with 32 bit FAT (LBA))
    start 63, size 61432497 (29996 Meg), flag 0
	beg: cyl 0/ head 1/ sector 1;
	end: cyl 1023/ head 254/ sector 63
The data for partition 2 is:
sysid 165 (0xa5),(FreeBSD/NetBSD/386BSD)
    start 61432560, size 173003985 (84474 Meg), flag 80 (active)
	beg: cyl 1023/ head 255/ sector 63;
	end: cyl 1023/ head 254/ sector 63
The data for partition 3 is:
<UNUSED>
The data for partition 4 is:
<UNUSED>



# /dev/ad0s2:
8 partitions:
#        size   offset    fstype   [fsize bsize bps/cpg]
  a:   524288        0    4.2BSD        0     0     0 
  b:  4194304   524288      swap                    
  c: 173003985        0    unused        0     0         # "raw" part, 
don't edit
  d:  1048576  4718592    4.2BSD        0     0     0 
  e:  1048576  5767168    4.2BSD        0     0     0 
  f: 104857600  6815744    4.2BSD        0     0     0 
  g: 61330641 111673344    4.2BSD        0     0     0 


The BIOS-LBA reads 14593/255/63 and in dmesg, next to ad0 it is 
232578/16/63. If I'm booting with the live CD I get:
Offset             Size(ST)             End
       0.................63...............1
      63...........61432497........61432559     ad0s1
61462560..........173003985.........23443644    ad0s2
234436545..............2990........234439543    unused

and the geometry 14593/255/63


The obvious question ;-/ what can I do to get my system up or at least 
back-up my /home ?


Thanks,
IOnut