yum-fs-snapshot btrfs howto?

[Chris Murphy]

On Jan 16, 2014, at 11:21 AM, Neal Becker <ndbecker2 at gmail.com> wrote:
> 
> I'm talking only about yum-fs-snapshot.

Yeah I haven't used it.

>  When I run yum it's never going to 
> write into /home.  But I don't know exactly what this means.

And when you do a yum update, do you get a snapshot in /home?

>  Notice my /home 
> and / root partition are the same physical device (which is fedora's default 
> install on btrfs - or at least was when I did the original install).

Yes.


> So I'm guessing yum-fs-snapshot will snapshot everything - since it does 
> snapshot or root.  Does additional snapshot of /home actually do anything?

I'm not sure what you mean by additional. What's the first instance? Snapshots do not recursively snapshot subvolumes. For example:

274	5517	5		<FS_TREE>/home.0
476	5344	5		<FS_TREE>/home.0/chris/Downloads/git
488	5352	5		<FS_TREE>/home.0/chris/Downloads/git/kernel


If I snapshot ID 274, the resulting subvolume will stop at a directory ./chris/Downloads/git which will be empty. So it's not going to contain any reference at all to the subvolumes that were in the original subvolume.


Chris Murphy