Arch Linux on a Lenovo Thinkpad P52s

I installed Arch Linux on a Lenovo Thinkpad P52s using btrfs for the filesystem and grub for the bootloader. I recorded my process, beginning in a fresh installation image environment and ending with the root user booting into the new system.

I drew from several sources. The sources all have slightly different goals and focus areas. Most offer a useful generality this document may lack.

Partitions

Hopefully already well understood, but always worth mentioning, these instructions delete all data on the disk. Device names may vary by system.

fdisk /dev/nvme0n1

The fdisk utility launches. It presents an interactive prompt.

• Delete any existing partitions. Enter d and accept the default partition repeatedly until no partitions remain.

• Create EFI partition. Enter n to create a new partition. Enter 1 for the partition number. Accept the default first sector. Enter +4G for the size. Then fdisk returns to its top-level prompt. Enter t to set the partition type. Enter 1 for the partition number. Enter uefi for the partition type.

• Create root partition. Enter n to create a new partition. Enter 2 for the partition number. Accept the default first sector. Accept the default size to use all remaining disk space.

• Write changes. Optionally enter p to display the changes. Enter w to write the changes to disk. Then fdisk exits automatically.

Two new devices /dev/nvme0np1 and /dev/nvme0np1 exist now, and correspond to the two new partitions.

Filesystems

Format the root partition with a btrfs filesystem to support snapshots. Ultimately only the subvolumes of this partition will be mounted, but for now temporarily mount it for the purpose of creating the subvolumes. Good candidates are parts of the filesystem that contain large or rapidly changing data unimportant for system restoration purposes. Create the subvolumes. The subvolumes appear under the partition's mount point as directories. Unmount the partition. Mount each of the subvolumes in its proper place. The noatime option improves performance by not tracking access times on files.

# Format the root partition
mkfs.btrfs /dev/nvme0n1p2

# Mount the partition temporarily
mount /dev/nvme0n1p2 /mnt

# Create subvolumes in the partition
btrfs su cr /mnt/@
btrfs su cr /mnt/@home
btrfs su cr /mnt/@root_btrsnap
btrfs su cr /mnt/@tmp
btrfs su cr /mnt/@var_cache
btrfs su cr /mnt/@var_log
btrfs su cr /mnt/@var_tmp

# Umount the partition
umount /mnt

# Mount the subvolumes
mount --mkdir -o noatime,compress=lzo,space_cache=v2,subvol=/@ /dev/nvme0n1p2 /mnt
mount --mkdir -o noatime,compress=lzo,space_cache=v2,subvol=/@home /dev/nvme0n1p2 /mnt/home
mount --mkdir -o noatime,compress=lzo,space_cache=v2,subvol=/@root_btrsnap /dev/nvme0n1p2 /mnt/root/btrsnap
mount --mkdir -o noatime,compress=lzo,space_cache=v2,subvol=/@tmp /dev/nvme0n1p2 /mnt/tmp
mount --mkdir -o noatime,compress=lzo,space_cache=v2,subvol=/@var_cache /dev/nvme0n1p2 /mnt/var/cache
mount --mkdir -o noatime,compress=lzo,space_cache=v2,subvol=/@var_log /dev/nvme0n1p2 /mnt/var/log
mount --mkdir -o noatime,compress=lzo,space_cache=v2,subvol=/@var_tmp /dev/nvme0n1p2 /mnt/var/tmp

Format the EFI parition with a FAT32 filesystem for compatibility with the firmware that will need to interact with it, and then mount the partition. The fmask and dmask options may help prevent certain nondescript boot issues I encountered.

mkfs.vfat -F32 /dev/nvme0n1p1
mount --mkdir -o fmask=0077,dmask=0077 /dev/nvme0n1p1 /mnt/efi

Installation

Connect to the internet wirelessly, replacing MyNetwork and MyPassphrase appropriately. Install the minimum necessary packages. Generate the fstab file. This file remembers where we mounted everything.

iwctl --passphrase MyPassphrase station wlan0 connect MyNetwork
pacstrap -K /mnt base linux linux-firmware
genfstab -U /mnt >> /mnt/etc/fstab

# Optionally take a snapshot
btrfs su snapshot /mnt /mnt/root/btrsnap/0000.base

Configuration

Enter into the new installation. Install iwd and openresolv for internet access without help from the installation image, the text editor vim for editing configuration files, and btrfs-progs for taking system snapshots. Go through a number of mundane steps per the installation guide.

arch-chroot /mnt
pacman -S iwd openresolv vim btrfs-progs

# Set root password
passwd

# Create /etc/localtime (replace MyRegion and MyCity appropriately)
ln -sf /usr/share/zoneinfo/MyRegion/MyCity /etc/localtime

# I didn't read up on what this does
hwclock --systohc

# Uncomment the appropriate UTF-8 line, generate locale(s)
vim /etc/locale.gen
locale-gen

Bootloader

Install the necessary packages to make a grub bootloader. Then install the bootloader and set up its configuration. Consider saving the bootloader installation and configuration lines as a script for later use.

pacman -S grub efibootmgr
grub-install --target=x86_64-efi --efi-directory=/efi --bootloader-id=arch_grub
grub-mkconfig -o /boot/grub/grub.cfg

# Optionally take a snapshot
btrfs su snapshot / /root/snapshots/0001.configure

Reboot

Exit out of the chroot, unmount all the filesystems, and restart the system.

# Back in the installation image environment
umount -R /mnt
reboot

Remove the installation media and restart the laptop. If all goes well log in as root.

References

• Official installation guide
  Authoritative and comprehensive, but also branches off in many directions. Complimentary resources demonstrating specific paths through the installation process can help.
• Michele Gementi's installation guide
  Primary resource after exploring many avenues because it treats an unencrypted btrfs filesystem. Concludes with a discussion of video drivers and preparation for playing games.
• Thomas Forgione's installation guide
  Uses ext4 filesystems, but features an encrypted /home partition. Discusses docker configuration, and measures to ensure the compatibility of the installation with wake-on-lan.
• Myyc's installation guide
  Single encrypted btrfs filesystem. Built in systemd bootloader instead of grub. Splash screen on startup and shutdown using plymouth. Covers setting up secure boot and hibernate.
• Vladimir Kaplarevic's swap post
  Discusses swap partitions and the practices surrounding them that several major Linux distributions have landed on. Also contains useful information about memory usage and monitoring.
• Brendan and others on the initial ramdisk
  Flow of control passes through a bootloader and an initial ramdisk before reaching the Linux kernel. Contributors discuss and critique why these components exist and what they do.