I am backing up data from an old hard drive one partition at a time to .img files using dd.
sudo dd if=/dev/sdc5 of=/home/flex/data/partition.img bs=1M status=progressThis gives me a 10GB .img file but I know there is only 3GB data on the partition.
The partition is FAT32 and contains a Windows XP OS.
I loop mount the .img file... it appears at /dev/loop7
sudo losetup --find partition.imgThen open in GParted..
sudo gparted /dev/loop7Now in Gparted when I go to resize the partition it appears to work and gives no errors but I don't think it actually changes anything. The .img file is still 10GB and this command shows that the size of the partition is still 10GB..
sudo parted /dev/loop7 unit s print freeI thought there would unallocated partition space that I could then do...
truncate --size=$[(End Sector+1)*512] partition.imgWhat am I doing wrong?
I guess my alternative is to TAR the whole partition.img and then extract to a blank .img file but I want to know if this method with GParted is possible because it seems like a convenient way to resize a .img file for storage.
Cheers,
Flex
1 Answer
My problem with GParted not re-sizing the partition was because of the way I was extracting each partition individually from my old hard drive each into a separate .img file for each partition.
sudo dd if=/dev/sdc5...
This was giving me a partition.img file that had no partition table or partition either, just the filesystem.
So now I follow these steps instead...
-- Create a blank .img file that is large enough to contain the partition you extract from the old HDD. E.g: 12GB.
sudo dd if=/dev/zero of=Win-XP-New-12G.img bs=1M count=12000-- Loop mount that file and find out what loop device it got with lsblk (/dev/loop7 in this case)
sudo losetup --find Win-XP-New-12G.img
lsblk-- Create a partition table in the 12GB .img file then create a partition then format that partition as fat32 (the partition I was archiving from the old HDD is FAT32)
sudo parted -s /dev/loop7 mklabel msdos
sudo parted -s /dev/loop7 mkpart primary fat32 2048s 100%
sudo mkfs -t vfat /dev/loop7p1-- With the old HDD connected to my Ubuntu laptop via USB I find the device file of the partition I want using lsblk-- Copy the data from the HDD partition /dev/sdc5 DIRECTLY INTO the PARTITION in the 12GB .img file. e.g: /dev/loop7p1 below
sudo dd if=/dev/sdc5 of=/dev/loop7p1 bs=1M status=progress-- Now open the device file that points to the 12GB .img file in GParted to re-size the partition to make it smaller. This time the GParted re-size worked and later I truncated the .img file Great help from here.
sudo gparted /dev/loop7I did not go with the tar or rsync commands because they do not preserve accessed or create timestamps when copying files to a Fat32 filessytem.
