It may be that only part of the filesystem has been shigted by 2 bytes. Look through the partition and see if you can find blocks that look kike proper files/signatures. If that's a case later on in the filesystem, then do a binary search to see if you can figure out where the boundry is between the shifted and unshifted parts. <div class="gmail_quote">On Wed, Dec 17, 2008 at 2:28 PM, Paul Raines <<a href="mailto:raines@nmr.mgh.harvard.edu">raines@nmr.mgh.harvard.edu</a>> wrote: <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> <div class="Ih2E3d">On Wed, 17 Dec 2008, Jon Burgess wrote: <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> On Wed, 2008-12-17 at 15:35 -0500, Paul Raines wrote: <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> Any fancy Linux device tricks I can do to make /dev/sdc1 shift everything by two bytes? </blockquote> losetup -o 2 e.g. [root@shark ~]# od -t x1 /dev/sda | head -n 1 0000000 eb 48 90 10 8e d0 bc 00 b0 b8 00 00 8e d8 8e c0 [root@shark ~]# losetup -o 2 /dev/loop0 /dev/sda [root@shark ~]# od -t x1 /dev/loop0 | head -n 1 0000000 90 10 8e d0 bc 00 b0 b8 00 00 8e d8 8e c0 fb be Jon </blockquote> </div> Perfect! THanks. Unfortunately it appears the filesystem is toast though and it was not as simple as everything being shifted by 2 bytes. So I will chalk it up as a loss. [root@shadowfax ~]# losetup -o 2 /dev/loop7 /dev/sdc1 [root@shadowfax ~]# dumpe2fs -h /dev/loop7<div class="Ih2E3d"> dumpe2fs 1.39 (29-May-2006) </div> Filesystem volume name: ASALAZAR_USB1 Last mounted on: <not available> Filesystem UUID: 549ade87-064b-46e8-8280-10c8a6f474b4 Filesystem magic number: 0xEF53 Filesystem revision #: 1 (dynamic) Filesystem features: resize_inode filetype sparse_super large_file Default mount options: (none) Filesystem state: not clean with errors Errors behavior: Continue Filesystem OS type: Linux Inode count: 61063168 Block count: 122096000 Reserved block count: 6104800 Free blocks: 46076684 Free inodes: 60915913 First block: 0 Block size: 4096 Fragment size: 4096 Reserved GDT blocks: 994 Blocks per group: 32768 Fragments per group: 32768 Inodes per group: 16384 Inode blocks per group: 512 Filesystem created: Thu Jun 26 13:03:39 2008 Last mount time: Tue Dec 16 15:31:21 2008 Last write time: Tue Dec 16 19:28:13 2008 Mount count: 35 Maximum mount count: 38 Last checked: Thu Jun 26 13:03:39 2008 Check interval: 15552000 (6 months) Next check after: Tue Dec 23 12:03:39 2008 Reserved blocks uid: 0 (user root) Reserved blocks gid: 0 (group root) First inode: 11 Inode size: 128 Default directory hash: tea Directory Hash Seed: e41ec746-def1-4d33-9a44-8aff8caef73b ext2fs_read_bb_inode: A block group is missing an inode table [root@shadowfax ~]# e2fsck -f -n /dev/loop7 e2fsck 1.39 (29-May-2006) Group descriptors look bad... trying backup blocks... e2fsck: Bad magic number in super-block while trying to open /dev/loop7 The superblock could not be read or does not describe a correct ext2 filesystem. If the device is valid and it really contains an ext2 filesystem (and not swap or ufs or something else), then the superblock is corrupt, and you might try running e2fsck with an alternate superblock: e2fsck -b 8193 <device><div><div></div><div class="Wj3C7c"> _______________________________________________ Ext3-users mailing list <a href="mailto:Ext3-users@redhat.com" target="_blank">Ext3-users@redhat.com</a> <a href="https://www.redhat.com/mailman/listinfo/ext3-users" target="_blank">https://www.redhat.com/mailman/listinfo/ext3-users</a> </div></div></blockquote></div> -- Stephen Samuel <a href="http://www.bcgreen.com">http://www.bcgreen.com</a> 778-861-7641