Grub-btrfs error

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I need a little help to set up BtrFS Assistant to work with grub-btrfs. I selected the automatic partitioning in Fedora 40. Everything else is default.

I git cloned grub-btrfs and followed Antynea’s instructions for Fedora of editing the /etc/default/grub-btrfs/config
But I am not sure I’ve uncommented everything that’s needed for Fedora, and I don’t want to bork it.

Here is what I changed in /etc/default/grub-btrfs/config so far:

#!/usr/bin/env bash


GRUB_BTRFS_VERSION=4.13-yabsnap_info_support-2024-03-06T13:43:57+00:00

# Disable grub-btrfs.
# Default: "false"
#GRUB_BTRFS_DISABLE="true"

# Name appearing in the Grub menu.
# Default: "Use distribution information from /etc/os-release."
GRUB_BTRFS_SUBMENUNAME="Fedora snapshots"

# Custom title.
# Shows/Hides "date" "snapshot" "type" "description" in the Grub menu, custom order available.
# Default: ("date" "snapshot" "type" "description")
#GRUB_BTRFS_TITLE_FORMAT=("date" "snapshot" "type" "description")

# Limit the number of snapshots populated in the GRUB menu.
Default: "50"
GRUB_BTRFS_LIMIT="50"

# Sort the found subvolumes by "ogeneration" or "generation" or "path" or "rootid".
# # See Sorting section to https://btrfs.wiki.kernel.org/index.php/Manpage/btrfs-subvolume#SUBCOMMAND
# "-rootid" means list snapshot by new ones first.
# Default: "-rootid"
#GRUB_BTRFS_SUBVOLUME_SORT="+ogen,-gen,path,rootid"

# Show snapshots found during run "grub-mkconfig"
# Default: "true"
#GRUB_BTRFS_SHOW_SNAPSHOTS_FOUND="false"

# Show Total of snapshots found during run "grub-mkconfig"
# Default: "true"
#GRUB_BTRFS_SHOW_TOTAL_SNAPSHOTS_FOUND="true"

# By default, "grub-btrfs" automatically detects most existing kernels.
# If you have one or more custom kernels, you can add them here.
# Default: ("")
#GRUB_BTRFS_NKERNEL=("kernel-custom" "vmlinux-custom")

# By default, "grub-btrfs" automatically detects most existing initramfs.
# If you have one or more custom initramfs, you can add them here.
# Default: ("")
#GRUB_BTRFS_NINIT=("initramfs-custom.img" "initrd-custom.img" "otherinit-custom.gz")

# By default, "grub-btrfs" automatically detects most existing microcodes.
# If you have one or more custom microcodes, you can add them here.
# Default: ("")
#GRUB_BTRFS_CUSTOM_MICROCODE=("custom-ucode.img" "custom-uc.img "custom_ucode.cpio")

# Additional kernel command line parameters that should be passed to the kernel
# when booting a snapshot.
# For dracut based distros this could be useful to pass "rd.live.overlay.overlayfs=1"
# or "rd.live.overlay.readonly=1" to the Kernel for booting snapshots read only.
# Default: ""
#GRUB_BTRFS_SNAPSHOT_KERNEL_PARAMETERS="rd.live.overlay.overlayfs=1"

# Comma separated mount options to be used when booting a snapshot.
# They can be defined here as well as in the "/" line inside the respective snapshots'
# "/etc/fstab" files.  Mount options found in both places are combined, and this variable
# takes priority over `fstab` entries.
# NB: Do NOT include "subvol=..." or "subvolid=..." here.
# Default: ""
#GRUB_BTRFS_ROOTFLAGS="space_cache,commit=10,norecovery"

# Ignore specific path during run "grub-mkconfig".
# Only exact paths are ignored.
# e.g : if `specific path` = @, only `@` snapshot will be ignored.
# Default: ("@")
GRUB_BTRFS_IGNORE_SPECIFIC_PATH=("@")

# Ignore prefix path during run "grub-mkconfig".
# Any path starting with the specified string will be ignored.
# e.g : if `prefix path` = @, all snapshots beginning with "@/..." will be ignored.
# Default: ("var/lib/docker" "@var/lib/docker" "@/var/lib/docker")
GRUB_BTRFS_IGNORE_PREFIX_PATH=("var/lib/docker" "@var/lib/docker" "@/var/lib/docker")

# Ignore specific type/tag of snapshot during run "grub-mkconfig".
# For snapper:
# Type = single, pre, post.
# For Timeshift:
# Tag = boot, ondemand, hourly, daily, weekly, monthly.
# For yabsnap:
# Trigger = S, I, U.
# Default: ("")
#GRUB_BTRFS_IGNORE_SNAPSHOT_TYPE=("")

# Ignore specific description of snapshot during run "grub-mkconfig".
# e.g: timeline
# Default: ("")
#GRUB_BTRFS_IGNORE_SNAPSHOT_DESCRIPTION=("")

# By default "grub-btrfs" automatically detects your boot partition,
# either located at the system root or on a separate partition or in a subvolume,
# Change to "true" if your boot partition isn't detected as separate.
# Default: "false"
#GRUB_BTRFS_OVERRIDE_BOOT_PARTITION_DETECTION="true"

# Location of the folder containing the "grub.cfg" file.
# Might be grub2 on some systems.
# Default: "/boot/grub"
GRUB_BTRFS_GRUB_DIRNAME="/boot/grub2"

# Location of kernels/initramfs/microcode.
# Use by "grub-btrfs" to detect the boot partition and the location of kernels/initrafms/microcodes.
# Default: "/boot"
#GRUB_BTRFS_BOOT_DIRNAME="/boot"

# Location where grub-btrfs.cfg should be saved.
# Some distributions (like OpenSuSE) store those files at the snapshot directory
# instead of boot. Be aware that this directory must be available for grub during
# startup of the system.
# Default: $GRUB_BTRFS_GRUB_DIRNAME
#GRUB_BTRFS_GBTRFS_DIRNAME="/boot/grub"

# Location of the directory where Grub searches for the grub-btrfs.cfg file.
# Some distributions (like OpenSuSE) store those file at the snapshot directory
# instead of boot. Be aware that this directory must be available for grub during
# startup of the system.
# Default: "\${prefix}" # This is a grub variable that resolves to where grub is
# installed. (like /boot/grub, /boot/efi/grub)
# NOTE: If variables of grub are used here (like ${prefix}) they need to be escaped
# with `\` before the `$`
#GRUB_BTRFS_GBTRFS_SEARCH_DIRNAME="\${prefix}"


# Name/path of grub-mkconfig command, use by "grub-btrfs.service"
# Might be 'grub2-mkconfig' on some systems (Fedora ...)
# Default paths are /sbin:/bin:/usr/sbin:/usr/bin,
# if your path is missing, report it on the upstream project.
# For example, on Fedora : "/sbin/grub2-mkconfig"
# You can use only name or full path.
# Default: grub-mkconfig
GRUB_BTRFS_MKCONFIG=/usr/bin/grub2-mkconfig

# Name of grub-script-check command, use by "grub-btrfs"
# Might be 'grub2-script-check' on some systems (Fedora ...)
# For example, on Fedora : "grub2-script-check"
# Default: grub-script-check
#GRUB_BTRFS_SCRIPT_CHECK=grub2-script-check

# Path of grub-mkconfig_lib file, use by "grub-btrfs"
# Might be '/usr/share/grub2/grub-mkconfig_lib' on some systems (Opensuse ...)
# Default: /usr/share/grub/grub-mkconfig_lib
#GRUB_BTRFS_MKCONFIG_LIB=/usr/share/grub2/grub-mkconfig_lib

# Password protection management for submenu,snapshots
# Refer to the Grub documentation https://www.gnu.org/software/grub/manual/grub/grub.html#Authentication-and-authorisation
# and this comment https://github.com/Antynea/grub-btrfs/issues/95#issuecomment-682295660
#
# Add authorized usernames separate by comma (foo,bar)
# When Grub's password protection is enabled, the superuser is authorized by default, it isn't necessary to add it
# Default: ""
#GRUB_BTRFS_PROTECTION_AUTHORIZED_USERS="foo,bar"
#
# Disable authentication support for submenu of Grub-btrfs only (--unrestricted)
# doesn't work if GRUB_BTRFS_PROTECTION_AUTHORIZED_USERS isn't empty
# Default: "false"
#GRUB_BTRFS_DISABLE_PROTECTION_SUBMENU="true"

Thanks in advance.

1 Like
2

I can say that the Snapper (Btrfs Assistant) - Grub-Btrfs (and inotify-tools) duo is not working as it is supposed to. So what is it supposed to be?

  1. Snapper automatically takes snapshots as configured by the user. Sometimes the user also takes snapshots manually through Snapper. Also Snapper automatically deletes old snapshots.
  2. Grub-Btrfs adds or removes these three processes as a list of bootable snapshots in the bootloader.
  3. To rollback system to one of the old snapshots, the user choose a read-only snapshot from the bootloader.
  4. Makes the writable version of the read-only snapshot the default via Snapper.
  5. The user reboots their system, still sees Grub-Btrfs’s list of bootable snapshots in the bootloader, making sure everything is where it should be, confirming that when the system starts it is in the exact snapshot they want to rollback to.

That’s what is experienced on openSUSE and that’s what the Snapper - Grub-Btrfs duo should promise, that’s what is supposed to happen. But in reality things break at step 5 and Grub-Btrfs no longer adds bootable snapshots to the bootloader.

I came across a video that claims that the Snapper - Grub-Btrfs duo works 100%, but as you can see at the end of this video, breaks down. Watch second video carefully, the last time he restarted the system there should have been 3 (or maybe 2) entries in the bootloader list but there are not. Before that he ran grub2-mkconfig, but even then not all snapshots were added to the bootloader. On openSUSE you don’t need to run grub2-mkconfig command every time.

3

Thanks for the reply. I feel you. I did see that video and its fancy editing at the end, which kind of disproved the video title.
Also I researched the problem until the wee hours, and could only find my own own unanswered posts. I think this is a dead issue unless the developer of Btrfs-Assistant chimes in, as I know he can walk me through it as he has done with EndeavourOS. Thanks for taking the time to confirm what many Fedorans already know.

4

@distro-nix If you are still enthusiastic, you can take a look at this guide. I haven’t tested it myself because the number of processing steps is a bit high.