1999-08-25 15:01:09

by Theodore Y. Ts'o

[permalink] [raw]
Subject: Re: Question: finding boundaries of ext2fs-partitions.

Date: Tue, 24 Aug 1999 05:38:25 +0200 (CEST)
From: Osman <[email protected]>

I heard from an other list that there was a discussion here a few weeks
ago or some, about this topic.
I need a prg wich will help me in rebuilding/recreating my partition
The data is still there, only the table was lost due to a mistake I made
while installing RH6.0.

The following list of tools that will allow you to rebuild partition
tables was written up by Andries Brouwer ([email protected]) a few
months ago, and as far as I know it's still an accurate description of
the various choices you have out there for this task.

In my personal opinion, gpart is probably the best of the bunch at this
point, although all of the programs are relatively new and aren't
foolproof. In particular, nearly all of them can be confused by
previous filesystems whose superblocks are still present on the disk.
(In the future, programs could be made smarter by looking at the mount
times to see which filesystem is more recent if there are two
overlapping filesystems. As far as I know none of the programs do this
kind of hueristics for you, so manual human judgement will be required.)

Anyway, here's Anderies's list:

(i) findsuper is a small utility that finds blocks with the ext2
superblock signature, and prints out location and some info.
It is in the non-installed part of the e2progs distribution.

(ii) rescuept is a utility that recognizes ext2 superblocks,
FAT partitions, swap partitions, and extended partition tables;
it prints out information that can be used with fdisk or sfdisk
to reconstruct the partition table.
It is in the non-installed part of the util-linux distribution.

(iii) fixdisktable (http://bmrc.berkeley.edu/people/chaffee/fat32.html)
is a utility that handles ext2, FAT, NTFS, ufs, BSD disklabels
(but not yet v1 Linux swap partitions); it actually will rewrite
the partition table, if you give it permission.

(iv) gpart (http://home.pages.de/~michab/gpart/) is a utility
that handles ext2, FAT, Linux swap, HPFS, NTFS, FreeBSD and
Solaris/x86 disklabels, minix, reiser fs; it prints a proposed
contents for the primary partition table, and is well-documented.

Hope this helps!

- Ted