Iso/dd image mounting howto

= Howto to mount an dd/iso image =

When disk fail/start failing it is sometimes necessary to create a backup of the hard drive using ddrescue (see ddrescue howto). This creates a bit for bit copy of the disk/file system.

To read the image you mount it via loopback

you might need to specify the file system e.g.

If this complains about not being able to find a file system it might be that a copy was made of an entire disc rather than partitions with in it.

In this run the command  -- this will output the partition table of the disk. Look up the number of the partition user the Start column.

This is a number expressed in blocks. Typically a block is 512 bytes so multiple this number by 512 to get the offset.

e.g.

You can also do e.g.:

In this case  is doing the multiplication for you.

This technique also works with iso images.

For use with Macs, and more setails om  see:Mac Backup Notes