Backing up sd card image on external usb drive

To continue the backup issue:
Why not use rsync to backup?
I’m aware that its not a backup of the whole sdcard, no image with empty space also backed up.
If there are Problems you’d just have to format the sdcard, create right file system and restore the backup again with rsync.
Someone enlighten a noob and tell me why this could be a bad idea and also whats the difference between a rsync backup (with all necessary and useful options) and dd backup…I mean I know dd is a bitwise copy, but I mean what’s the difference in practice?

I wouldn’t call it a bad idea. It is just not as convenient as a plain dd copy which is one command to restore.
But clearly the rsync backup has advantages:

  • you don’t waste space for the empty sectors
  • you can do it any time while the system is running
  • you can do it incremental with snapshots (allowing you to go back in time without waste of space)

So doing a backup of your partition scheme to be able to replay that and having a script to transfer backup your rsync files would definitely be a good approach as long as you know how to.

If you compress a dd backup using gzip or whatever the empty space compresses nicely and the space taken is greatly reduced. In Windows USBIT will make a compressed iso backup and write a compressed file back to the card. Last time I looked this feature is missing from Win32 Imager

This is where the pros come into play :grinning:
No… I currently have a rsync backup command I use with --delete and --numeric-ids, etc. option and I leave out unnecessary directories (the ones that get polluted automatically for instance)…
I run from ssh every time and didn’t look into automation yet. I know I need a script and cronjob but if I do it I want it to be with weekly backups and monthly and in a way where the old backups get deleted every 3 weeks or so etc…
Would be nice if this could be done with a osmc app :slightly_smiling: