Good morning all, in today’s episode of “What I learned during work hours”…
I was playing around with wxHexEditor and realised that if something catastrophic happened, I would really struggle with any data recovery if I lost the inode tables for any drive.
A quick duckle pointed me to e2image, which says in the man:
It is a very good idea to create image files for all file systems on a system and save the partition layout (which can be generated using the fdisk -l command) at regular intervals — at boot time, and/or every week or so.
I couldn’t find any prebuilt solutions for this online, so I wrote a systemd service and timer to do this for me. I save the fdisk to a text file, run e2image on a couple drives, and compress it all together in a dated 7z that can get uploaded via rsync or Mega or Dropbox etc.
The metadata image from a 500gb drive is 8gb, but compresses down to 40mb. Backup takes a couple minutes.
Unfortunately this does not work with my raid drives, but they are RAID1 so already resilient.
Apparently I was being a derp somehow. …Anyways,
My RAID drives are 16TB, e2image of this is 125gb, and 7z’d it comes down to just 63mb.
I’ll post the service, timer, and backup script in a comment, let me know if you can spot anywhere for improvements!
Sure, all the work you do between the moment of the filesystem failure and the last backup is gone. There’s nothing that can be done to mitigate that fact, other that more frequent backups and/or a synchronized (mirror) system.
Backups are just a simple way to keep you from having to explain to your partner that you lost all the pictures and videos you took along the years.