Is the encrypt-hook required when used for root partition?

[francoism90]

Bit confused; is it needed to set the encrypt hook before filesystems to unlock a root filesystem?
I've got troubles in the past when not using the udev hook, is it required to remove this hook?

What does the a function do? Because now I had to use s, run cryptsetup luksOpen .. to get a working boot process. Or should the / be added to /etc/crypttab?

Thanks. :)

[Andrei-Pozolotin]

1. here is recommended hook list for mkinitcpio.conf:

HOOKS="base autodetect modconf block filesystems keyboard fsck systemd systemd-tool"

2. sample content of /boot/initramfs-linux.img/ucpio://etc/crypttab:

# <mapper name> <block device> <password/keyfile> <crypto options>
# root
root   UUID=342d9e07-c09e-4a36-bbbf-03ea8bfb1647   none   luks,discard
# swap
swap   UUID=567def65-29c1-420c-91c2-37be2d63545e   none   luks,discard

3. sample content of

/etc/fstab:

# <block device>  <mount point> <fs type> <options> <dump> <pass>
# root
/dev/mapper/root   /   auto   defaults,nofail,noatime   0   1
# swap
/dev/mapper/swap   none   swap   defaults,nofail,noatime   0   2
# boot
UUID=939D-4331   /boot   auto   defaults,nofail,noatime   0   2
# home
/dev/mapper/home   /home   auto   defaults,nofail,noatime   0   2

/etc/crypttab:

# <mapper name> <block device> <password/keyfile> <crypto options>
home   UUID=6f16e925-dcdc-412c-80e4-3ad2bb9bb5fa   /etc/crypttab.d/keyfile.bin   luks,discard,key-slot=7,nofail

4. finally:

lsblk:

NAME     MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
sda        8:0    0 465.8G  0 disk  
├─sda1     8:1    0   499M  0 part  /boot
├─sda2     8:2    0   4.9G  0 part  
│ └─swap 254:0    0   4.9G  0 crypt [SWAP]
└─sda3     8:3    0 460.4G  0 part  
  └─root 254:1    0 460.4G  0 crypt /
sr0       11:0    1  1024M  0 rom 

blkid:

/dev/sda1: UUID="939D-4331" TYPE="vfat" PARTUUID="2fe9b9a8-01"
/dev/sda2: UUID="567def65-29c1-420c-91c2-37be2d63545e" TYPE="crypto_LUKS" PARTUUID="2fe9b9a8-02"
/dev/sda3: UUID="342d9e07-c09e-4a36-bbbf-03ea8bfb1647" TYPE="crypto_LUKS" PARTUUID="2fe9b9a8-03"
/dev/mapper/swap: UUID="6de529e0-45e4-40f1-ab04-184b42a42dc1" TYPE="swap"
/dev/mapper/root: UUID="cbf95c88-b91a-437a-a52d-47db427ea8b5" TYPE="ext4"

[stephenmk]

My root partition lives in an LVM inside a LUKS container. I found that I had to add an LVM hook to mkinitcpio.conf to get it to work.

HOOKS="base autodetect modconf block sd-lvm2 filesystems keyboard fsck systemd systemd-tool"

Just wanted to share this information in case others have the same issue. Thank you!

[benzinrts]

@stephenmk, thanks for the hint!
I use LVM residing on RAID, so I had to add mdadm hook. Hook order is important and the below one worked for me:
base autodetect modconf block filesystems keyboard fsck systemd mdadm_udev sd-lvm2 systemd-tool