If you’ve cloned a whole drive using dd and you need to access one of the partitions on it here are some steps to follow in order to gain access:
Find the partition start sectors using fdisk -b512 -l. Note that you’re explicitly setting the sector size to 512 bytes and you’ll need to change your command to match your own image file.
fdisk -b512 -l backup_sata.img
You should get output similar to this (note I’ve truncated it to only show the appropriate output):
Device Boot Start End Sectors Size Id Type backup_sata.img1 * 2048 206847 204800 100M 7 HPFS/NTFS/exFAT backup_sata.img2 206848 237185023 236978176 113G 7 HPFS/NTFS/exFAT backup_sata.img3 237185024 588070911 350885888 167.3G f W95 Ext'd (LBA) backup_sata.img4 588070912 625137663 37066752 17.7G 27 Hidden NTFS WinRE backup_sata.img5 237187072 588070911 350883840 167.3G 7 HPFS/NTFS/exFAT
Normally sector are 512 bytes, so you can calculate the offset you need in the next command with:
start * 512 = offset
So if you want to mount backup_sata.img5 (partition 5 of the backup image) you’d run 237187072×512=121439780864:
mount -o ro,loop,offset=121439780864 backup_sata.img /backup_sata
Remember to have created /backup_sata or whatever directory you’re mounting to first!