documentation/docs/gentoo-desktop-setup/provisioning.md

To install Gentoo this guide will be using the Alpine Extended Iso. It provides all of the necessary utilities for bootstrapping Gentoo and is overal pleasant to work with. Make sure to boot with Secureboot in setup mode or to already have keys ready to deploy.

After booting the Alpine Linux extended ISO, partition the disks. For this action internet is required since zfs, sgdisk and various other necessary packages are not included on the extended ISO, therefore they need to be obtained from the alpine package repository.

To set it up setup-interfaces and setup-apkrepos will be used.

sh# setup-interfaces -ar
sh# setup-apkrepos -c1

To use Wi-Fi simply run setup-interfaces -r and select wlan0 or similar.

A few packages will have to be installed first,

sh# apk add zfs lsblk sgdisk wipefs dosfstools

and load the ZFS kernel module

sh# modprobe zfs

Wipe the existing disk partitions

sh# zpool labelclear -f /dev/<disk>
sh# wipefs -a /dev/<disk>
sh# sgdisk --zap-all /dev/<disk>

Create on the disk an EFI system partition (ESP) and a Linux filesystem partition

sh# sgdisk -n 1:1m:+512m -t 1:ef00 /dev/<disk>
sh# sgdisk -n 2:0:-10m -t 2:8300 /dev/<disk>

Reload the device nodes

sh# mdev -s

Then, format the ESP with a FAT32 filesystem

sh# mkfs.fat -F 32 -n esp /dev/<disk>1

ZFS pool creation

The ZFS system pool is going to be encrypted. First generate an encryption key and save it temporarily to the file /tmp/rpool.key with:

sh# cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 20 | head -n 1 > /tmp/rpool.key && cat /tmp/rpool.key

Later on in the guide zlevis will be used for automatic decryption, so this key only has to be entered a few times. However, if any changes are made to the bios or secureboot then this key will be needed again, so make sure to save it.

Create the system pool:

sh# zpool create -f \
        -o ashift=12 \
        -O compression=lz4 \
        -O acltype=posix \ 
        -O xattr=sa \
        -O dnodesize=auto \
        -O encryption=on \
        -O keyformat=passphrase \
        -O keylocation=prompt \
        -m none \
        rpool /dev/<disk>2

Then create the system datasets:

sh# zfs create -o mountpoint=none rpool/root
sh# zfs create -o mountpoint=legacy -o quota=48g rpool/root/gentoo
sh# zfs create -o mountpoint=legacy -o quota=32g rpool/root/gentoo/var
sh# zfs create -o mountpoint=/home -o atime=off -o setuid=off -o devices=off -o quota=<home-quota> rpool/home

Setting the <home-quota> depends on the total size of the pool, generally try to reserve some empty space in the pool.

sh# zpool export rpool