System Installation

1. Partition the disks:

   for i in ${DISK}; do
   
   # wipe flash-based storage device to improve
   # performance.
   # ALL DATA WILL BE LOST
   # blkdiscard -f $i
   
   sgdisk --zap-all $i
   
   sgdisk -n1:1M:+1G -t1:EF00 $i
   
   sgdisk -n2:0:+4G -t2:BE00 $i
   
   sgdisk -n4:0:+${INST_PARTSIZE_SWAP}G -t4:8200 $i
   
   if test -z $INST_PARTSIZE_RPOOL; then
       sgdisk -n3:0:0   -t3:BF00 $i
   else
       sgdisk -n3:0:+${INST_PARTSIZE_RPOOL}G -t3:BF00 $i
   fi
   
   sgdisk -a1 -n5:24K:+1000K -t5:EF02 $i
   
   sync && udevadm settle && sleep 3
   
   cryptsetup open --type plain --key-file /dev/random $i-part4 ${i##*/}-part4
   mkswap /dev/mapper/${i##*/}-part4
   swapon /dev/mapper/${i##*/}-part4
   done
   

2. Create boot pool:

   zpool create \
       -o compatibility=grub2 \
       -o ashift=12 \
       -o autotrim=on \
       -O acltype=posixacl \
       -O canmount=off \
       -O compression=lz4 \
       -O devices=off \
       -O normalization=formD \
       -O relatime=on \
       -O xattr=sa \
       -O mountpoint=/boot \
       -R /mnt \
       bpool \
       mirror \
       $(for i in ${DISK}; do
          printf "$i-part2 ";
         done)
   

   If not using a multi-disk setup, remove mirror.

   You should not need to customize any of the options for the boot pool.

   GRUB does not support all of the zpool features. See spa_feature_names in grub-core/fs/zfs/zfs.c. This step creates a separate boot pool for /boot with the features limited to only those that GRUB supports, allowing the root pool to use any/all features.

   Features enabled with -o compatibility=grub2 can be seen here.

3. Create root pool:

   zpool create \
       -o ashift=12 \
       -o autotrim=on \
       -R /mnt \
       -O acltype=posixacl \
       -O canmount=off \
       -O compression=zstd \
       -O dnodesize=auto \
       -O normalization=formD \
       -O relatime=on \
       -O xattr=sa \
       -O mountpoint=/ \
       rpool \
       mirror \
      $(for i in ${DISK}; do
         printf "$i-part3 ";
        done)
   

   If not using a multi-disk setup, remove mirror.

4. Create root system container:

   • Unencrypted:

     zfs create \
      -o canmount=off \
      -o mountpoint=none \
      rpool/archlinux
     

   • Encrypted:

     Pick a strong password. Once compromised, changing password will not keep your data safe. See zfs-change-key(8) for more info:

     zfs create \
      -o canmount=off \
      -o mountpoint=none \
      -o encryption=on \
      -o keylocation=prompt \
      -o keyformat=passphrase \
      rpool/archlinux
     

   You can automate this step (insecure) with: echo POOLPASS | zfs create ....

   Create system datasets, let Archlinux declaratively manage mountpoints with mountpoint=legacy:

   zfs create -o mountpoint=/ -o canmount=noauto rpool/archlinux/root
   zfs mount rpool/archlinux/root
   zfs create -o mountpoint=legacy rpool/archlinux/home
   mkdir /mnt/home
   mount -t zfs rpool/archlinux/home /mnt/home
   zfs create -o mountpoint=legacy  rpool/archlinux/var
   zfs create -o mountpoint=legacy rpool/archlinux/var/lib
   zfs create -o mountpoint=legacy rpool/archlinux/var/log
   zfs create -o mountpoint=none bpool/archlinux
   zfs create -o mountpoint=legacy bpool/archlinux/root
   mkdir /mnt/boot
   mount -t zfs bpool/archlinux/root /mnt/boot
   mkdir -p /mnt/var/log
   mkdir -p /mnt/var/lib
   mount -t zfs rpool/archlinux/var/lib /mnt/var/lib
   mount -t zfs rpool/archlinux/var/log /mnt/var/log
   

5. Format and mount ESP:

   for i in ${DISK}; do
    mkfs.vfat -n EFI ${i}-part1
    mkdir -p /mnt/boot/efis/${i##*/}-part1
    mount -t vfat ${i}-part1 /mnt/boot/efis/${i##*/}-part1
   done
   
   mkdir -p /mnt/boot/efi
   mount -t vfat $(echo $DISK | cut -f1 -d\ )-part1 /mnt/boot/efi