Arch Linux

happyhyppo

Member

Registered: 2021-09-29

Posts: 1

Boot stuck when booting a btrfs snapshot

Hi everyone,

I followed some tutorial on yt (by a serious guy, don't worry - EFLinux channel) to install arch with btrfs and snapshots + snap-pac-grub.

As I'm coming from openSuse, I wanted to enjoy the peace of mind of knowing that if I mess up something, I can easily boot to a previous state.

Now, while I get all the snapshots listed in the grub menu of my arch install, whenever I try to boot one of those, I get the usual Started arch-version
And then the block of text warning that the root partition could not be mounted in read-write mode.

Nothing happens after that.

Could you please help?

I would like snapshots to be bootable, and of course I'd like to be able to confirm that I want to rollback to a specific snapshot permanently, if I like what I see.

Thanks!

[andrea@inspiron ~]$ lsblk
NAME        MAJ:MIN RM   SIZE RO TYPE MOUNTPOINTS
nvme0n1     259:0    0 238.5G  0 disk 
|-nvme0n1p1 259:1    0   976M  0 part /boot/efi
|-nvme0n1p2 259:2    0    25G  0 part /.snapshots
|                                     /
|-nvme0n1p3 259:3    0  67.5G  0 part /home
|-nvme0n1p4 259:4    0     8G  0 part [SWAP]
|-nvme0n1p5 259:5    0  60.1G  0 part 
`-nvme0n1p6 259:6    0  76.9G  0 part

[andrea@inspiron ~]$ cat /etc/fstab 
# Static information about the filesystems.
# See fstab(5) for details.

# <file system> <dir> <type> <options> <dump> <pass>
# /dev/nvme0n1p2
UUID=1bb338f0-9bd1-473b-944e-93fb9a95479a       /               btrfs           rw,noatime,compress=lzo,ssd,space_cache=v2,subvolid=256,subvol=/@       0 0

# /dev/nvme0n1p3
UUID=795f1bc7-d381-4c19-860c-d884dfa70ce3       /home           ext4            rw,relatime     0 2

# /dev/nvme0n1p2
UUID=1bb338f0-9bd1-473b-944e-93fb9a95479a       /.snapshots     btrfs           rw,noatime,compress=lzo,ssd,space_cache=v2,subvolid=257,subvol=/@snapshots      0 0

# /dev/nvme0n1p1
UUID=2994-BCF5          /boot/efi       vfat            rw,relatime,fmask=0022,dmask=0022,codepage=437,iocharset=ascii,shortname=mixed,utf8,errors=remount-ro   0 2

subvolumes:

[andrea@inspiron ~]$ sudo btrfs subvol list /
ID 256 gen 1727 top level 5 path @
ID 257 gen 1725 top level 5 path @snapshots
ID 258 gen 18 top level 256 path var/lib/portables
ID 259 gen 19 top level 256 path var/lib/machines
ID 282 gen 169 top level 257 path @snapshots/22/snapshot
ID 287 gen 282 top level 257 path @snapshots/27/snapshot
ID 322 gen 382 top level 257 path @snapshots/62/snapshot
ID 323 gen 383 top level 257 path @snapshots/63/snapshot
ID 324 gen 394 top level 257 path @snapshots/64/snapshot
ID 325 gen 395 top level 257 path @snapshots/65/snapshot
ID 327 gen 436 top level 257 path @snapshots/67/snapshot
ID 328 gen 439 top level 257 path @snapshots/68/snapshot
ID 329 gen 449 top level 257 path @snapshots/69/snapshot
ID 330 gen 450 top level 257 path @snapshots/70/snapshot
ID 331 gen 458 top level 257 path @snapshots/71/snapshot
ID 332 gen 459 top level 257 path @snapshots/72/snapshot
ID 333 gen 465 top level 257 path @snapshots/73/snapshot
ID 334 gen 466 top level 257 path @snapshots/74/snapshot
(truncated)

And this is a random entry in /boot/grub/grub-btrfs.cfg:

submenu 'Snapshot: 2021-09-30 09:20:01  @snapshots/73/snapshot  | pre    | pacman -S man' {
    submenu '---> Snapshot: 2021-09-30 09:20:01  @snapshots/73/snapshot  | pre    | pacman -S man <---' { echo }

    menuentry 'vmlinuz-linux & initramfs-linux-fallback.img' --class snapshots --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-snapshots-1bb338f0-9bd1-473b-944e-93fb9a95479a' {
        if [ x$feature_all_video_module = xy ]; then
        insmod all_video
        fi
        set gfxpayload=keep
        insmod btrfs
        if [ x$feature_platform_search_hint = xy ]; then
            search --no-floppy --fs-uuid  --set=root  1bb338f0-9bd1-473b-944e-93fb9a95479a
        else
            search --no-floppy --fs-uuid  --set=root 1bb338f0-9bd1-473b-944e-93fb9a95479a
        fi
        echo 'Loading Snapshot: 2021-09-30 09:20:01 @snapshots/73/snapshot'
        echo 'Loading Kernel: vmlinuz-linux ...'
        linux "/@snapshots/73/snapshot/boot/vmlinuz-linux" root=UUID=1bb338f0-9bd1-473b-944e-93fb9a95479a  loglevel=3 quiet rootflags=rw,noatime,compress=lzo,ssd,space_cache=v2,subvol="@snapshots/73/snapshot"
        echo 'Loading Initramfs: initramfs-linux-fallback.img ...'
        initrd "/@snapshots/73/snapshot/boot/initramfs-linux-fallback.img"
    }

    menuentry 'vmlinuz-linux & initramfs-linux.img' --class snapshots --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-snapshots-1bb338f0-9bd1-473b-944e-93fb9a95479a' {
        if [ x$feature_all_video_module = xy ]; then
        insmod all_video
        fi
        set gfxpayload=keep
        insmod btrfs
        if [ x$feature_platform_search_hint = xy ]; then
            search --no-floppy --fs-uuid  --set=root  1bb338f0-9bd1-473b-944e-93fb9a95479a
        else
            search --no-floppy --fs-uuid  --set=root 1bb338f0-9bd1-473b-944e-93fb9a95479a
        fi
        echo 'Loading Snapshot: 2021-09-30 09:20:01 @snapshots/73/snapshot'
        echo 'Loading Kernel: vmlinuz-linux ...'
        linux "/@snapshots/73/snapshot/boot/vmlinuz-linux" root=UUID=1bb338f0-9bd1-473b-944e-93fb9a95479a  loglevel=3 quiet rootflags=rw,noatime,compress=lzo,ssd,space_cache=v2,subvol="@snapshots/73/snapshot"
        echo 'Loading Initramfs: initramfs-linux.img ...'
        initrd "/@snapshots/73/snapshot/boot/initramfs-linux.img"
    }
}

bluewolf

Member

Registered: 2022-01-04

Posts: 2

Re: Boot stuck when booting a btrfs snapshot

I searched to sort this issue over the entire internet, i installed and reinstalled the entire operating system but nothing, it's stuck after
[OK] Account Service
blinking |

nothing, if i want to login in TTY I don't have any problem

(i think is a issue with gdm)  but I don't know how to fix.