On 08/24/2010 11:44 PM, Tavian Barnes wrote: > On 24 August 2010 16:02, Mauro Santos <registo.mailling@xxxxxxxxx> wrote: >> On 08/24/2010 10:20 PM, Marek Otahal wrote: >>> On Tuesday 24 of August 2010 23:03:23 Mauro Santos wrote: >>>> On 08/24/2010 08:14 PM, Marek Otahal wrote: >>>>> Hi all, >>>>> >>>>> I use dd command to make an image of entire /dev/sda (160GB) and back up >>>>> it as netobook.hdd to an external storage. The disk contains both >>>>> encrypted(dmcrypt/luks) and normal linux/win partitions. >>>>> >>>>> My question is, if my netbook died and I needed to recover from backup, >>>>> can I just dd-copy the image to a new larger disk? Does it matter? >>>>> >>>>> 1/ it will do, but the size will remain 160gb ..is ok. >>>>> 2/ will do & possibility to resize partitions later ..even better! :) >>>>> >>>>> I've searched the net, but I'd like someone to confirm it 100% works >>>>> (just dd and reboot). >>>>> >>>>> Thanks in advance, Marek >>>> >>>> Most probably you don't even need to copy the image back to a disk to >>>> get the files you need. I don't know about the encrypted(dmcrypt/luks) >>>> partitions but the "normal" linux/win partitions can be accessed >>>> directly from the image. >>> >>> Is that so? I like the restore to a functional computer ability, so copying >>> seems useful. But I was wondering how to mount a specific partition from an >>> image? (i make the image of whole /dev/sda, so sda1,2,..are hidden inside) >>> >>> greetings, Marek >> >> Usually I do it like this: >> - mount (?) the image to a loop device >> losetup /dev/loop0 /path/to/image/file >> >> - get the start of partitions >> parted /dev/loop0 unit B print >> >> take notice of the starting bytes for the partition you want to mount >> mount /dev/loop0 mnt_point -o offset=start_bytes >> >> and thats it, you should be able to access at least the "normal" >> partitions (read and write). I have never tried with encrypted >> partitions, I guess you would have to pass some extra options to mount. >> >> To unmount everything cleanly do: >> umount mnt_point >> losetup -d /dev/loop0 >> >> -- >> Mauro Santos >> > > But why? The loop module supports partitions now, just modprobe it > with max_part=10 or something. The partitions will be > /dev/loop0p[1234...]. > Nice tip. I've been using this method for quite a while so either it wasn't available when I started using it or I missed the fact that the module option is needed for this to work. -- Mauro Santos
