I would like to make manual backups of an SD card as a disk image so that it can be easily recreated when needed. I’d like to keep a few versions in case there is a problem I didn’t know about, it can be rolled back.

How can I do this incrementally, or with de-duplication, so that I don’t have to keep full copies of the complete SD card? It’s very big but most of the content won’t be changing much.

It’s for MiyooCFW ROM which is on FAT 32-formatted micro SD card.

Thanks for your help! Also let me know if I am going about the problem in a wrong way.

  • NeoNachtwaechter@lemmy.world
    2·
    4 months ago

    I haven’t tried such a thing, but I remember ZFS has an option for block deduplication.

    So you would set up a ZFS with block deduplication (and probably without compression - try this point out), and then you make your backup images with the dd tool and the correct block size.

    Now you make always full copies and have them as normal files but they take only the disk space of the differences.

    let me know if I am going about the problem in a wrong way.

    I would not say “wrong way”. I’s fun to think about such things and try them out.

    On the other hand I think a FAT32 can have only 32Gb. I would not mind having many of them lying around on my home NAS that has 12 Tb on RAID :-)