back up (BTRFS questions)

[nicrnicr]

Dear All,

If I well understood, Grey Geek wrote that a btrfs partition is wonderful because roll backs are very easy. Is rolling back the contrary to backing up please?
https://www.kubuntuforums.net/forum/...l=1#post403412

What are the @, @_old or @home please? Do we have te create them? What are snapshots (snapshots of @ and @home) please?

[oshunluvr]

There's literally dozens of posts here about using BTRFS. GG and I and others have written many pages of info. You should probably search the forum for BTRFS and find the Wiki page on the Arch site and read up.

Briefly, to your questions:
A "rollback" is to replace the subvolume currently in use with a previous snapshot of the same subvolume. It is a simple as renaming the current subvolume and the snapshot and rebooting. Literally takes about 10 seconds.

Making a backup of a subvolume is to copy it entirely to a different BTRFS file system - usually on a different drive.

Subvolumes can be named whatever you like, but the names used by default at installation are @ and @home. @ being the system files and @home being the home folder (for all users).

The installer created the initial subvolumes of @ and @home. If you desire snapshots you have to create them yourself or use an available tool like Snapper. I do not use third party tools as I prefer to do things my way.

Before you can do either snapshots or backups of subvolumes, you must first mount the root file BTRFS system as it is not mounted by default. Once you have mounted the root FS, you will be able to see @ and @home subvolumes and make your snapshots and backups.

[nicrnicr]

Thank you very much oshunluvr!! :-)

[jlittle]

... btrfs is wonderful because roll backs are very easy. Is rolling back the contrary to backing up please?

"rollback" means booting to a snapshot taken at some previous time. A snapshot is not a backup; if the drive fails, or the filesystem is irretrievably corrupted, the systems and data in the btrfs are gone.

On other distros they're going fully into automatic snapshots and rolling back with a GUI with just a few clicks, but with the integrity of my system involved, I'll stick to performing the steps manually, for now anyway. It takes no time; with conventional backups, it means copying the system from the backup (though, using rsync might not take a lot of time) and overwriting the current system (with btrfs it's still there).

btrfs is wonderful for actual backups, too, but that's another story.

[nicrnicr]

Thank you very much jlittle. I've much to learn..