grub-btrfs

This is a version 4.xx of grub-btrfs

BTC donation address:

1Lbvz244WA8xbpHek9W2Y12cakM6rDe5Rt

Description :

Improves Grub by adding "btrfs snapshots" to the Grub menu.

You can boot your system on a "snapshot" from the Grub menu.
Supports manual snapshots, snapper, timeshift ...

Warning: booting on read-only snapshots can be tricky

If you choose to do it,

/var/log

/var

This project includes its own solution.
Refer to the documentation.

What does grub-btrfs v4.xx do :

• Automatically List snapshots existing on root partition (btrfs).
• Automatically Detect if "/boot" is in separate partition.
• Automatically Detect kernel, initramfs and intel/amd microcode in "/boot" directory on snapshots.
• Automatically Create corresponding "menuentry" in

  grub.cfg

• Automatically detect snapper and use snapper's snapshot description if available.
• Automatically generate

  grub.cfg

  if you use the provided systemd service.

Installation :

Arch Linux

The package is available in the community repository grub-btrfs

pacman -S grub-btrfs

Gentoo

grub-btrfs is only available in the Gentoo User Repository (GURU) and not in the official Gentoo repository.
If you have not activated the GURU yet, do so by running:

emerge -av app-eselect/eselect-repository 
eselect repository enable guru 
emerge --sync 

Now merge grub-btrfs via

emerge app-backup/grub-btrfs

Manual

• Run

  make install

  or look into Makefile for instructions on where to put each file.
• Dependencies:
  • btrfs-progs
  • grub

NOTE: All distros

Generate your Grub menu after installation for the changes to take effect.
For example:
On Arch Linux or Gentoo use

grub-mkconfig -o /boot/grub/grub.cfg

grub2-mkconfig -o /boot/grub2/grub.cfg

update-grub

grub-mkconfig ...

Customization :

You have the possibility to modify many parameters in

/etc/default/grub-btrfs/config

Automatically update grub :

Systemd

1. If you would like grub-btrfs menu to automatically update when a snapshot is created or deleted:
2. Use

   systemctl enable grub-btrfs.path

   .

   • grub-btrfs.path

     automatically (re)generates

     grub-btrfs.cfg

     when a modification appears in

     /.snapshots

     mount point (by default).
   • If the

     /.snapshots

     mount point is already mounted, then use

     systemctl start grub-btrfs.path

     to start monitoring.
     Otherwise, the unit will automatically start monitoring when the mount point will be available.

3. If your snapshots location aren't mounted in

   /.snapshots

   , you must modify

   grub-btrfs.path

   unit using
   

   systemctl edit --full grub-btrfs.path

   and run

   systemctl reenable grub-btrfs.path

   for changes take effect.
   To find out the name of the

   .mount

   unit
   use

   systemctl list-units -t mount

   .

   • For example: Timeshift mounts its snapshot folder in

     /run/timeshift/backup/timeshift-btrfs/snapshots

     .

     Use

     systemctl edit --full grub-btrfs.path

     . Then replace the whole block by: ``` [Unit] Description=Monitors for new snapshots DefaultDependencies=no Requires=run-timeshift-backup.mount After=run-timeshift-backup.mount BindsTo=run-timeshift-backup.mount

     [Path] PathModified=/run/timeshift/backup/timeshift-btrfs/snapshots

     [Install] WantedBy=run-timeshift-backup.mount ``

     Then save and finally run

     systemctl reenable grub-btrfs.path

     for changes take effect.  
     Optional:  
     If the

     /run/timeshift/backup/timeshift-btrfs/snapshots

     mount point is already mounted,  
     then use

     systemctl start grub-btrfs.path` to start monitoring.
     Otherwise, the unit will automatically start monitoring when the mount point will be available.

   • You can view your change to

     systemctl cat grub-btrfs.path

     .

   • To revert change use

     systemctl revert grub-btrfs.path

     .

4. If you would like grub-btrfs menu to automatically update on system restart/shutdown:
   Look at this comment
   Currently not implemented

   OpenRC

5. There is sadly no similar solution to the systemd service yet.
   As a workaround it is possible to add a script to

   /etc/local.d

   to execute the snapshot menu update every time you shut down your system.
   To do so just add the following script as

   /etc/local.d/grub-btrfs-update.stop

   ```

   !/bin/bash

   description="Update the grub btrfs snapshots menu" name="grub-btrfs-update"

   depend() { use localmount }

   bash -c 'if [ -s "${GRUBBTRFSGRUBDIRNAME:-/boot/grub}/grub-btrfs.cfg" ]; then /etc/grub.d/41snapshots-btrfs; else {GRUBBTRFSMKCONFIG:-grub-mkconfig} -o {GRUBBTRFSGRUB_DIRNAME:-/boot/grub}/grub.cfg; fi' ```

   If you want to run the menu update on startup instead, rename the file to

   grub-btrfs-update.start

Warning :

by default,

grub-mkconfig

grub2-mkconfig

GRUB_BTRFS_MKCONFIG

/etc/default/grub-btrfs/config

Special thanks for assistance and contributions

• Maxim Baz
• Schievel1
• All contributors - - -