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ricardomv / snapper-gui

GUI for snapper, a tool for Linux filesystem snapshot management, works with btrfs, ext4 and thin-provisioned LVM volumes
GNU General Public License v2.0
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User Interface: Which option is for LVM thin volume snapshots? #65

Open averyfreeman opened 3 months ago

averyfreeman commented 3 months ago

Hi,

appologies if you're not maintaining this software anymore -

Questions:

  1. I was just wondering if you meant "LVM" instead of "KVM" in the interface, for the drop-down menu to select which kind of drive,

    or if "EXT4" is the "LVM" option

    It's not really clear which one is for LVM, since none of the 3 listed in the dropdown are named 'LVM'

  2. Also, I saw in another one of your github issues where someone mentioned "EXT4" functionality has been removed. Is that true that "EXT4" no longer works, does that mean your GUI no longer tracks snapper's thin-LVM snapshots?

  3. Lastly, LVM thin snapshots work a little "backwards". When a snapshot is taken, the volume where the main filesystem resides - let's call it: /dev/mapper/vgroup-lvol The thin-lv identified by VG/LV = vgroup/lvol is what gets frozen from the snapshot, and becomes read-only. When we made the snapshot, let's say we called it vgroup/lvol-may31st-20h04m That dev (the mountable one) would be at /dev/mapper/vgroup-lvol-may31st-20h04m, but the mount point where /dev/mapper/vgroup-lvol will have been replaced by it.

    What I'm trying to say is, vgroup/lvol will stop changing and be read-only. IT is the "snapshot". vgroup/lvol-may31st-20h04m (which looks like a "snapshot") keeps growing after a snapshot is taken.

    I have tested this myself by creating snapshots and immediately making disk images from the vgroup/lvol mount point, because since it's read only, it doesn't change, and can be done while the system is live without problems.

    Anyway, I know that can be a little confusing, so I just wanted to let you know.

    Thanks for any info you'd like to give me, hope you're having a nice day -Avery