What am I thinking is:
I have sdd and hdd.
I would like to have / and /home as separate partitions on SDD
HDD is going to be backup drive.
Installation - architect
Lets say that there is a big update for manjaro.
I would like to create snapshot (probably read only) of / on my HDD
Assume that something during update goes wrong.
First thing that came to my mind is tu use rsync
rsync -aAXv /......./backup/ /
Can it work?
Any better way?
While m-a installation there is an option to do something with root and home (@/, @home). Don't remember the name but If I'm correct it mounts root and home as subvolumes. Is it necessary to my "backup" solution?
If I'm correct btrfs COW works like that:
I have /data/subvolume1 with files f1, f2, f3...
When I create snapshot of subvolume1 on HDD there are no f1,...,f3 copy on HDD until I change or delete them from subvolume1.
So during system update I'll not have a real backup on my HDD but only files that were changed during an update.
So I can't just copy files from snapshot to root because It's not an exact copy. This is where rsync idea came.