Arch Linux LUKS2 + LVM root fails to boot: timed out waiting

arpapa1236 · 2026-08-18 12:38:49

I'm installing Arch Linux in a VirtualBox VM, and I'm trying to set up a system with an encrypted root filesystem.

My intended storage layout is:
GPT
├── EFI system partition
└── LUKS2
└── LVM physical volume
└── volume group
└── logical volume (root)
└── ext4

The EFI system partition is unencrypted. The /boot directory is part of the root filesystem, so /boot is located inside the LUKS2 container.
The system installs successfully, but it fails to boot. GRUB appears normally, the LUKS password is requested, and LUKS is unlocked successfully. After that, however, the system hangs while waiting for the LVM logical volume containing the root filesystem:
[ TIME ] Timed out waiting for device /dev/mapper/VG_root-root.
[DEPEND] Dependency failed for /sysroot.
[DEPEND] Dependency failed for Initrd Root File System.
[DEPEND] Dependency failed for Initrd Root Device.
[DEPEND] Dependency failed for File System Check on /dev/mapper/VG_root-root.

I have tried a completely fresh Arch Linux installation with the same LUKS2 → LVM → root layout, but I get exactly the same boot failure.
My current configuration includes the `sd-encrypt` and `lvm2` mkinitcpio hooks, and the kernel command line contains the LUKS UUID.

The result of executing certain commands inside arch-chroot /mnt:

[root@archiso /]# lsblk -o NAME,TYPE,FSTYPE,FSVER,LABEL,UUID,PARTUUID,SIZE,MOUNTPOINTS
NAME               TYPE  FSTYPE      FSVER            LABEL       UUID                                   PARTUUID                               SIZE MOUNTPOINTS
loop0              loop  squashfs    4.0                                                                                                      955.7M
sda                disk                                                                                                                          10G
├─sda1             part  vfat        FAT32                        B9A1-CD41                              646a80f9-6654-46a5-b3ea-001e217ee923   100M /efi
└─sda2             part  crypto_LUKS 2                            969f212d-9003-4d07-a9c1-39ba69a0a18c   55d2e82b-b016-464c-a84d-602c43c35043   9.9G
  └─crypt          crypt LVM2_member LVM2 001                     P8VNli-fF1H-QRFU-oC1p-oge9-hbXh-QnvnRk                                        9.9G
    └─VG_root-root lvm   ext4        1.0                          a02ad752-865d-4f4a-955e-f16d260a501d                                            5G /
sr0                rom   iso9660     Joliet Extension ARCH_202603 2026-03-01-10-44-11-00                                                        1.4G

[root@archiso /]# blkid
/dev/mapper/VG_root-root: UUID="a02ad752-865d-4f4a-955e-f16d260a501d" BLOCK_SIZE="4096" TYPE="ext4"
/dev/sr0: BLOCK_SIZE="2048" UUID="2026-03-01-10-44-11-00" LABEL="ARCH_202603" TYPE="iso9660" PTUUID="f177ce2f" PTTYPE="dos"
/dev/loop0: BLOCK_SIZE="1048576" TYPE="squashfs"
/dev/mapper/crypt: UUID="P8VNli-fF1H-QRFU-oC1p-oge9-hbXh-QnvnRk" TYPE="LVM2_member"
/dev/sda2: UUID="969f212d-9003-4d07-a9c1-39ba69a0a18c" TYPE="crypto_LUKS" PARTUUID="55d2e82b-b016-464c-a84d-602c43c35043"
/dev/sda1: UUID="B9A1-CD41" BLOCK_SIZE="512" TYPE="vfat" PARTUUID="646a80f9-6654-46a5-b3ea-001e217ee923"

[root@archiso /]# pvs
  PV                VG      Fmt  Attr PSize PFree
  /dev/mapper/crypt VG_root lvm2 a--  9.88g 4.88g

[root@archiso /]# vgs
  VG      #PV #LV #SN Attr    VSize VFree
  VG_root   1   1   0 wz--n-- 9.88g 4.88g

[root@archiso /]# lvs
  LV   VG      Attr       LSize Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  root VG_root -wi-ao---- 5.00g

[root@archiso /]# cat /etc/fstab
# /dev/mapper/VG_root-root
UUID=a02ad752-865d-4f4a-955e-f16d260a501d       /       ext4    rw,relatime     0 1

# /dev/sda1
UUID=B9A1-CD41  /efi    vfat    rw,relatime,fmask=0022,dmask=0022,codepage=437,iocharset=ascii,shortname=mixed,utf8,errors=remount-ro                                                        0 2

[root@archiso /]# cat /etc/mkinitcpio.conf | grep HOOKS
HOOKS=(base systemd autodetect microcode modconf kms keyboard sd-vconsole block sd-encrypt lvm2 filesystems fsck)

[root@archiso /]# cat /etc/default/grub | grep GRUB_CMDLINE_LINUX
GRUB_CMDLINE_LINUX_DEFAULT="loglevel=3 quiet rd.luks.name=969f212d-9003-4d07-a9c1-39ba69a0a18c:crypt_lvm rd.lvm.lv=VG_root/root root=/dev/mapper/VG_root-root"
GRUB_CMDLINE_LINUX=""

Lone_Wolf · 2026-08-18 17:07:00

Try omitting the rd.lvm.lv=VG_root/root part . That should trigger lvm to mount of all lvm pv/vg/lv it can find .

arpapa1236 · 2026-08-20 13:01:12

I had already tried booting without the rd.lvm.lv=VG_root/root parameter; I only added it during my most recent attempts. I just removed it from the GRUB menu entry and tried booting again, but the result was the same.

Lone_Wolf · 2026-08-20 13:21:32

hmm, my luks2 on lvm setup is setup similar but I'm using refind and the encrypt hook with openbox in initram stage.

I'm not using /dev/mapper/VG1-root but /dev/VG1/root .
Does using root=/dev/VG_root/root help ?

Arch Linux

#1 2026-08-18 12:38:49

Arch Linux LUKS2 + LVM root fails to boot: timed out waiting

#2 2026-08-18 17:07:00

Re: Arch Linux LUKS2 + LVM root fails to boot: timed out waiting

#3 2026-08-20 13:01:12

Re: Arch Linux LUKS2 + LVM root fails to boot: timed out waiting

#4 2026-08-20 13:21:32

Re: Arch Linux LUKS2 + LVM root fails to boot: timed out waiting

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