Linux – faster dd backup by differential copy

backupddexternal hard driveincremental-backuplinux

im looking to use dd to back up my whole hard drive regularly but it takes around 1.5 hours and want to know if there is a faster way to back up.

possibly just by updating the bytes which are different.

Best Answer

You can backup a single LVM partition (not a whole raw disk as you mention but may still meet your requirements) by taking a snapshot of it, then doing a incremental backup of the filesystem rather than the raw disk. Once you have the snapshot, you could use incremental tar backups or rsync (recommend rsync). You dont strictly need the snapshot - or the LVM, but helps ensure you get a ~point in time filesystem image.

rsnapshot (which is basically a big wrapper on rsync to make it easier to do incremental backups) supports LVM snapshots and incremental backups. I use it to do the above. Note the first sync is still going to take a long time.