Manipulation of dd output file from partition

[jaymax]

FreeBSD 9.x. Disk fails to mount! I have copied the disk partition [MBR] from /dev/, the of - seems unreadable. No errors reported.

gpart show of disk:

  63  156344517     1  freebsd  [active]  (74G)

I have tried this on copied output (of) and on the input file (if) /dev/ada4 and /dev/ada4s1.
==>

dd if=ada4s1 conv=ascii of=asci_ada4s1 bs=1m

in an attempt to see if it can be converted to ASCII text format, - still unreadable.

Does anyone have any idea

1. how to make it humanly readable?
2. how to extract or possibly save portions of it? or
3. should I discard the dd() approach and use dump() instead?

 

[wblock@]

So what format is the data? Is it a UFS filesystem? Is it several tied up in bsdlabel(8)s? If you can identify that, it can be mounted with mdconfig(8).

Once again, dump(8) is the way to do this. A mysterious 74G binary is not a good way to save data.

 

[Crivens]

Once again, dump(8) is the way to do this. A mysterious 74G binary is not a good way to save data.

Please keep in mind that dump(8) only works on UFS file systems. Things like FAT or ZFS are not handeld.

 

[wblock@]

ZFS can send snapshots. The point is that it's better to use a filesystem-aware tool to copy or back up data. Once that high-level data is backed up, it can be restored (even to other filesystems) or accessed more easily.