Btrfs before install notes

Set up BTRFS before install, according to this guide

(You are booted in the Arch Live environment meant to install Arch on your machine or VM)

Contents 1 Before Pacstrap 1.1 Partitionning 1.2 Formatting 1.3 Start mounting and playing with BTRFS (04:50)

Before Pacstrap

loadkeys for your keyboard

Select device with fdisk -l ; VM devices starts with V here, as in /dev/vda1 et

Partitionning

fdisk /dev/vda

• Use g to create a GPT partition table on /dev/vda1

• Use n to create a first EFI partition

• Use +300M to make it 300M in size

• Use t to change its type to 1 to make it an EFI partition

• Use n to create a second partition for the rest of the disk

• Use p to check for values and mistakes

• Use w to write the modifications and exit the interactive fdisk prompt

Formatting

• mkfs.fat -F 32 /dev/vda1
• mkfs.btrfs /dev/vda2

Start mounting and playing with BTRFS (04:50)

• mount /dev/vda2 /mnt

• create subvolumes with

btrfs subvolume create /mnt/@
btrfs subvolume create /mnt/@home
btrfs subvolume create /mnt/@snapshots

• Check your existing subvolumes and their ID :

btrfs subvolume list /

(Reminder : subvolumes don't create snapshots of nested subvolumes ; here @ won't contain @home or @snapshots data)

• Create mountpoints

mkdir /mnt/efi
mkdir /mnt/home
mkdir /mnt/.snapshots
mkdir /mnt/btrfsroot

• Then Umount the actual /dev/vda2 to replace by the @ subvolume