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Setup Arch Linux with Simple DM-Crypt + LUKS on EFI Board with SSD
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arch-linux-plain-dmcrypt-setup.md

Setup Arch Linux with Simple DM-Crypt + LUKS on EFI Board with SSD

Read the Official Arch Installation Guide.

Done and tested with a new Thinkpad T490s.

Fetch and Burn Arch.iso

Download image and .sig files from here: https://www.archlinux.org/download/

$ gpg --keyserver-options auto-key-retrieve --verify archlinux-<VERSION>-x86_64.iso.sig
$ dd if=archlinux-<VERSION>-x86_64.iso of=/dev/sdX bs=16M && sync

Boot from Stick

Disable secure boot (newer BIOS + pre-installed Windows machines have that).

Get Intenet

$ wifi-menu

Wipe Disk

Be sure the disk is the right disk to wipe! Open a crypto container on the disk, zero it, and close the crypto container. See the drive-preparation wiki for more details.

$ cryptsetup open --type plain -d /dev/urandom /dev/nvme0n1 wipeme
$ dd if=/dev/zero of=/dev/mapper/wipeme status=progress bs=4M
$ cryptsetup close wipeme

Partition Disk

$ fdisk /dev/nvme0n1
# create EFI boot partition: n .... 512M .... t .... 1 (= EFI partition)
# use the rest for system partition (t 83)

It should look somewhat like this:

$ lsblk
# NAME          MAJ:MIN RM    SIZE  RO TYPE  MOUNTPOINT
# nvme0n1       259:0    0    477G   0 disk  
# ├─nvme0n1p1   259:1    0    512M   0 part  
# └─nvme0n1p2   259:2    0  476.4G   0 part

Format Boot Partition

mkfs.fat -F32 /dev/nvme0n1p1

Full-Disk Encryption

This follows plain LUKS_on_a_partition instructions.

Check cryptsetup --help and cryptsetup benchmark as your SSD might operate better with non-defaults.

The following command will prompt you for the disk password. We will call the disk cryptroot.

$ cryptsetup --use-random luksFormat /dev/nvme0n1p2
$ cryptsetup luksOpen /dev/nvme0n1p2 cryptroot

After this, your crypto disk is to be found under /dev/mapper/cryptroot

Virtual Partitions

You might want to read about LVM.

Note: When you have LVM partition/s, make sure to format and mount them instead of cryptroot in the following.

Format Partition/s

$ mkfs.ext4 -L root /dev/mapper/cryptroot

Mount

$ mount /dev/mapper/cryptroot /mnt      # arch will install here, on encrypted drive
$ mkdir /mnt/boot
$ mount /dev/nvme0n1p1 /mnt/boot        # unencrypted boot partition

Install Arch

You can alter the package bundles. linux will give you the standard kernel.

$ pacstrap /mnt base base-devel linux linux-firmware efibootmgr intel-ucode dialog wpa_supplicant zsh vim git sudo

Genfstab

$ genfstab -U /mnt >> /mnt/etc/fstab

If you have an SSD, consider changing relatime to noatime in the fstab for non-boot partitions. See FSTab atime_options.

Enter the New System

$ arch-chroot /mnt

Clock

$ ln -s /usr/share/zoneinfo/Europe/Berlin /etc/localtime
$ hwclock --systohc

Hostname & Hosts

$ echo MY_HOSTNAME > /etc/hostname

See the official installguide#network_configuration for /etc/hosts file details.

Localization

Uncomment your locale/s in /etc/locale.gen

$ vim /etc/locale.gen                           # e.g., en_US.UTF-8
$ locale-gen
$ localectl set-locale LANG=en_US.UTF-8
$ echo LANG=en_US.UTF-8 >> /etc/locale.conf

User Setup

$ passwd                                                            # root password
$ useradd -m -g users -G wheel,power -s /bin/zsh <YOUR_USER_NAME>
$ passwd <YOUR_USER_NAME>                                           # password for you user

Sudo Setup

Modify the sudoer's file and give your user appropriate rights

$ visudo
# e.g., <YOUR_USER_NAME> ALL=(ALL) ALL

Configure mkinitcpio

$ vim /etc/mkinitcpio.conf

Important:

  • If you have virtual partitions in your crypto volume, i.e., you are using LVM, you must add the lvm2 hook.
  • If you have a swap partition, read about hibernation and the resume hook.

Build initrd

Build kernel with your wanted presets

$ mkinitcpio -p linux   # for linux preset
$ mkinitcpio -P         # for all presets (per default there should only be `linux`)

Install Missing Firmware

You may encounter warnings like WARNING: Possibly missing firmware for module XXX:

For thinkpad t490s I got:

  • wd719x
  • aic94xx

Install them via AUR if possible or directly from git. Note: do this as non-root user. I prefer to use yay for installing AUR packages.

Install yay

Yay is an AUR helper (like yaourt). It's written in Go, new, fast, actively maintained...

$ su - <YOUR_USER_NAME>                             # take identity of your user
$ git clone https://aur.archlinux.org/yay.git
$ cd yay
$ makepkg -si
$ exit                                              # exit your user, switches back to root

Note: In case you installed missing firmware, don't forget to call mkinitcpio -P again, to create the initrd properly.

Systemd-boot (gummiboot)

See the configuration wiki.

$ bootctl --path=/boot install
$ echo default arch >> /boot/loader/loader.conf             # name `arch`. You can change that
$ echo timeout 3 >> /boot/loader/loader.conf
$ echo console-mode max >> /boot/loader/loader.conf
$ echo editor no >> /boot/loader/loader.conf

Create Bootloader Entry with Name arch

$ touch /boot/loader/entries/arch.conf                      # config must have name as your `default` in `/boot/loader/loader.conf`

Find out your disk UUID for /dev/nvme0n1p2. (Take a photo, you have to type that in.)

$ blkid

Replace <YOUR_UUID> with the UUID of /dev/nvme0n1p2.

See the adding_loaders wiki. See also the wiki for SSD kernel parameters.

$ vim /boot/loader/entries/arch.conf

title Arch Linux
linux /vmlinuz-linux
initrd /intel-ucode.img
initrd /initramfs-linux.img
options cryptdevice=UUID=<YOUR_UUID>:cryptroot root=/dev/mapper/cryptroot rw

Exit, Unmount All, and Reboot

$ exit
$ umount -R /mnt
$ reboot            # remove thumbdrive before reboot

Troubleshooting

You can always come back with the live-iso, in case you messed something up.

Boot again from the stick, then luksOpen the device. Mount the mapped device accordingly to /mnt. Don't forget to mount /mnt/boot. Afterwards you can continue whereever you mixed up your installation/config.

$ cryptsetup luksOpen /dev/nvme0n1p2 cryptroot
$ mount /dev/mapper/cryptroot /mnt
$ mount /dev/nvme0n1p1 /mnt/boot
$ arch-chroot /mnt
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