Support #492
Updated by Daniel Curtis over 9 years ago
While modifying the stock image of Raspbian, I decided to take a backup image of my drive using dd: dd if=/dev/sdb of=modified-raspbian.img Then shrunk main partition image to the value I desired using gparted: gparted modified-raspbian.img However the image of the entire drive left a lot of unallocated space left in the image. After searching online I found that all I needed to do was to use dd to extract just the raspbian image apart from the unallocated space. The parameter for dd that does this is count=. * Get the needed block information by running the following: <pre> fdisk -u -l modified-raspbian.img </pre> #* Example output: <pre> Disk /dev/sdb: 8462 MB, 8462008320 bytes 255 heads, 63 sectors/track, 1028 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x5c0894d9 Device Boot Start End Blocks Id System /dev/sdb1 * 1 9 72261 e W95 FAT16 (LBA) /dev/sdb2 10 103 755055 83 Linux </pre> * In the following example the last partition ends on 103, and the unit size is 8225280 bytes. So simply run command: <pre> dd if=modified-raspbian.img if=modified-raspbian of=modified-raspbian-stripped.img bs=8225280 count=103 </pre> #* *NOTE*: I had problems with a couple of images being corrupt after this process, so I found that adding 1 to the count argument will correct this. <pre> dd if=modified-raspbian.img if=modified-raspbian of=modified-raspbian-stripped.img bs=8225280 count=104 </pre> h2. Resources * http://serverfault.com/questions/446529/create-image-of-a-usb-drive-without-unallocated-partition