On Wednesday, May 19, 2010, C Anthony Risinger wrote: > On Wed, May 19, 2010 at 6:56 AM, kreij...@libero.it <kreij...@libero.it> wrote: > > Hi Anthony, > > > > I think that for you may be interested to read this thread > > > > http://kerneltrap.org/mailarchive/linux-btrfs/2009/11/20/6588643/thread > > > > and to read a my blog about this argument > > > > http://kreijack.blogspot.com/2010/01/linux-btrfs-example-of-layout.html > > > > Regards > > Goffredo > > thanks for the pointers, however the thread doesn't really offer a > solution or an indication of whether this will/can be possible :-(, > and your blog basically comes to the same conclusion that i already > agree with; the system should be installed into a subvolume from day > 1. i could be mistaken here, but in my experience, you cannot remove > a subvolume that has another subvolume within it. thus, setting a new > default subvolume doesn't actually change the heirarchy of subvolumes, > and since the original default subvol (.) contains all other > subvolumes, it still cannot be removed, as it's the ultimate parent > subvolume (even though it's not necessarily the default anymore). is > this correct?
On the basis of my experiences I agree with you. I think that it was not a good design to link the subvolumes to directory entries. I prefer that the subvolumes live in a different namespace, and it were mounted when required. > i need a way, programmatically and safely, to "move" the users > installation from the original subvolume into an isolated subvolume > called __active (what you called "rootfs" in you thread/blog), or to > generate a new, empty default/root subvolume and place the current > default subvol (.) _into_ it... how can this be done? until i figure > this out i have to tell the user to manually remove the stagnant files > from the dot (.) subvolume (usr/etc/lib...), since i don't think my > users would appreciate me issuing an "rm -rf" against their system. > > any other ideas/input? I am not sure to have understood well. But a possible solution may be to - snapshot the default subvolume to a rootfs. - boot in the rootfs subvolume - mount the default subvol (mount -o subvol=default /dev/sdX /mnt/default) - remove (carefully) the file under the default subvolume except the subvolume(s) (something like rm --one-file-system /mnt/default/). > > C Anthony > > ps. a recursive snapshotting tool could be useful too (if / and /home > were both subvols, the tool would create both when / was snapped, > instead of /home being an empty folder in the snapshot). > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- gpg key@ keyserver.linux.it: Goffredo Baroncelli (ghigo) <kreij...@inwind.it> Key fingerprint = 4769 7E51 5293 D36C 814E C054 BF04 F161 3DC5 0512 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
