Mouting file systems contained within a RAW disk image

To do this we will firstly need to identify where the partition we are interested in starts. This can be obtained from fdisk or parted - for example:

parted /path/to/disk.img

u # to change unit to bytes
B

p # to print partition table

Number  Start  End           Size          File system  Flags
 1 ... ... ... ... ...
 2      4238229B     53687091199B  53687091200B  xfs

In this case we are interested in partition 2 - so we'd set the offset in the mount command as 4238229:

mount -o loop,offset=4238229 /path/to/disk.img /mount/part2

The loop option is a pseudo device that acts as a block based device.

If like me you didn't have the luxury of a partition table to work from you can identify the start sector of the partition with testdisk e.g.:

testdisk /path/to/disk.img

and then perform the conversion of sectors to bytes:

expr <sectors> \* <sector-size>

e.g.:

expr 123456 \* 512 = 63209472

mount -o loop,offset=63209472 /path/to/disk.img /mount/part2