Raspberry Pi SDCard backup - Only used space...

[Meractik]

Ive got a very large 32gb SD card for my Raspberry Pi and I wish to copy it as a backup and also have the ability to mirror the card to another *smaller* SDCard, I use less then 700MB on the 32GB card because it simply houses my Raspberry Pi bootable stuff and is used exclusively with the Raspberry Pi only. I have all the settings perfected and would find it difficult to try & replicate them to a smaller card all over (Hence the reason I wish to mirror)


I was totally new to the whole Raspberry Pi stuff when I started fiddling with it and had no idea how impractical it would be to have such a large SDCard, therefore I wish to make a backup of the card and restore it to a much smaller card and use that to boot the Pi, and recycle the large 32GB card for something more suitable.


Any help you can provide is greatly appreciated, I am hoping their are some linux commands I could utilize to make this happen that would take a nice bit-by-bit backup and allow the use of switches to only extract/compress the used space? I am just unaware of them... If I had too I would also be okay with using some windows software if it can accomplish my needs.

Any help you can provide is greatly appreciated.

 

[Red Squirrel]

You can probably use something like Acronis.

Or, a more crude way, dd it to an existing 32GB card, use gparted to shrink down the partition, then dd the partition itself to a file. I have not tried this myself but I would imagine it should work.

I'm thinking something like acronis would be the easiest though. There's a free imaging program called clonezilla, it might work (never used it myself).

 

[Cerb]

Use Clonezilla for a one-off. Just have it plugged in to a PC with an SD reader, and voila!

Partclone will copy only used data on FSes it supports (and is what Clonezilla uses, if it can).
https://wiki.archlinux.org/index.php/Partclone
With 700MB, I wouldn't bother compressing it in-flight.

Thing is, you want to have it not be mounted writable, so it's easiest/safest to use another computer to do it, even if it will work on the RPi itself (I don't know that it will, but that wouldn't surprise me).

 

[Meractik]

Red Squirrel, I just tried Acronis since I have a bootable CD-Rom handy and it does see the SDCard as removable media and allow me to perform a backup (into a *.tib) file when I restore that backup to the smaller SDCard and place it in the Raspberry Pi it fails to boot from it. Going to give Clonezilla a try now...