2016-03-23 18:41 GMT+01:00 Vytautas D <vyt...@gmail.com>: > I can think of few ways to revert changes with btrfs, but I wonder > what are the trade-offs between each method and perhaps there is > already research done on this? > > ways to restore a snapshot ( post kernel 3.* ): > a) via set-default > 1. btrfs subvolume set-default / $id
Usually snapshots are readonly because we want the ability to use btrfs send/receive and not mistakenly change anything on them (such as atime). Also, this might break some configurations not expecting the set-default method. > 2. reboot > b) always mount into snapshot > 1. mount -o suvol=/.current $disk # at initrd > 2. btrfs subvol del /.current > 3. btrfs subvol snapshot /.snapshotA /.current > 4. reboot > c) rsync > 1. rsync $options /.snapshotA /.current > 2. reboot Depending on how broken the setup is, I'd probably go for the btrfs sub snap ./__snapshots/@oldsnap ./@current approach. If it is very broken (as in not bootable), then a temporary boot into a readonly snapshot might be required. This is quite easy to do in the grub menu, changing the boot parameter. I've also heard of symlinking to the actual subvolume you want to use, and resymlink it when an older snapshot is desired. > > - Vytas Dauksa > -- > 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 -- 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
