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rlake · 19 May 2002, 03:24

The program dd ("disk dump") really is just a raw block read/write utility so it'll work with any block device be it a hard disk, floppy disk or whatever. To create an image of an Amiga hard disk, it reads absolutely everything from block 0 through to the end, and just directs it to a file. So, the file is very similar to a HDF used by UAE except that a "real" hard disk is a superset of an HDF because it also contains partition information.

There is no chance the image is compressed/modified by dd but thanks for the concern anyway - of course, there's nothing stopping the use of zip/lha etc. on the resulting file but it's not worth it.

After a bit of reading I now believe block size conversion won't be necessary for 2 reasons:

- Commodore seem to have allowed scope for change but using a "fixed" size of 512 bytes would appear to be fine. I may be wrong about this but it doesn't matter because it's unaffected by the following...

- When restored, the drive and its partitions will have the same configuration as when it was backed up. The only difference is that restoring a 100 MB backup to an 8 GB drive will leave 7.9 GB of unpartitioned space at the end. Hopefully such waste can be avoided simply by running HDtoolbox or similar to create new partitions!
:laugh

Anyway, it looks like dd will do the job and I seem to have discovered an answer to my own question and managed to convince myself it'll work!

As long as there is Linux, SCSI, and my trusty Amiga HD backup CD I should be able to get my Amiga up and running in no time following FD/HD failure!

19 May 2002, 03:24	#8
rlake Hittin' the hardware... Join Date: Feb 2002 Location: Mountain View, CA Age: 44 Posts: 156	The program dd ("disk dump") really is just a raw block read/write utility so it'll work with any block device be it a hard disk, floppy disk or whatever. To create an image of an Amiga hard disk, it reads absolutely everything from block 0 through to the end, and just directs it to a file. So, the file is very similar to a HDF used by UAE except that a "real" hard disk is a superset of an HDF because it also contains partition information. There is no chance the image is compressed/modified by dd but thanks for the concern anyway - of course, there's nothing stopping the use of zip/lha etc. on the resulting file but it's not worth it. After a bit of reading I now believe block size conversion won't be necessary for 2 reasons: - Commodore seem to have allowed scope for change but using a "fixed" size of 512 bytes would appear to be fine. I may be wrong about this but it doesn't matter because it's unaffected by the following... - When restored, the drive and its partitions will have the same configuration as when it was backed up. The only difference is that restoring a 100 MB backup to an 8 GB drive will leave 7.9 GB of unpartitioned space at the end. Hopefully such waste can be avoided simply by running HDtoolbox or similar to create new partitions! :laugh Anyway, it looks like dd will do the job and I seem to have discovered an answer to my own question and managed to convince myself it'll work! As long as there is Linux, SCSI, and my trusty Amiga HD backup CD I should be able to get my Amiga up and running in no time following FD/HD failure!