On 04/10/2013 11:12 PM, John Gomez wrote:
I have a 500GB HD encrypted with LUKS, partitioned with LVM (I think) and formatted ext4. The /boot partition is on a USB stick. I want to make a backup of the HDD. Say my first drive is /sda and the backup drive is /sdx and I want the backup to go in /sdx3. AFAIK, I have two choices; 1: Create an encrypted partition on /sdx say, /sdx3, mount and decrypt /sda, then use rsync to copy the filesystem from /sda to /sdx3. Not the worst choice but there are flaws. What if I want to do this over a network?
Why is that an issue? rsync will, by default, use ssh for the communication.
What if I want to do this on /sdx that is already partitioned? (If /sdx is already partitioned I can not encrypt the partition /sdx3. Is this correct?)
Merely partitioned wouldn't be a problem, but if that partition already contains a filesystem and data you want to preserve, then converting it to encrypted would be a problem. Recent versions of the cryptsetup package do have the option to build an experimental cryptsetup-reencrypt tool that can encrypt an existing partition, but it's a long and delicate process.
2: Use dd (or GNU ddrescue or similar) using the parameters if=/sda of=/sdx3/backup.img. Then the problems are: how do I view the files? This post describes mounting an image of a partition: http://www.rebelzero.com/howto/backup-and-restore-files-tofrom-a-luks-encrypted-partition-image-file/189. Does anyone know a better way to do this? Will this work for an image of the entire drive?
You can work with the whole drive image, but it's a bit complicated, and the steps depend on exactly how the source drive was set up and whether LVM is involved. The basic tools are "losetup" to map a loop device to a file and "kpartx" to create device maps for the partitions within a device. I can't comment on the steps needed if LVM is involved. -- Bob Nichols "NOSPAM" is really part of my email address. Do NOT delete it. _______________________________________________ dm-crypt mailing list dm-crypt@xxxxxxxx http://www.saout.de/mailman/listinfo/dm-crypt