Note: This guide isn't actively maintained and some information might be old
arch-btrfs-install-guide
This is an Arch UEFI installation guide with btrfs and snapper. This guide doesn't contain all the information needed to install Arch. It is meant to be used with the Arch installation guide on the Arch wiki, it only contains the diffrences for installing btrfs and snapper, and some other tips. The btrfs and snapper setup is based on this guide from unicks.eu https://www.youtube.com/watch?v=TKdZiCTh3EM. I recommend watching the video from unicks.eu, watching an Arch Linux installation tutorial. My favorite Arch Linux UEFI installation tutorial was from Average Linux User(https://www.youtube.com/watch?v=dOXYZ8hKdmc)
This guide is meant to be used with the Arch installation guide on the Arch wiki.
Reminders:
Double check what is the drives name you want to install on, it might not be /dev/sda. You need to install the userspace utilities for the different filesystems(xfsprogs, btrfs-progs, dosfstools). You can use ssh to connect to the computer you are installing Arch Linux on, so you can save time by copying the commands.
Ssh
I recommend connecting both of your devices to the same network because it will be much easier to connect with ssh to the computer you are installing Arch on. If you don't know what ssh is and how to connect from a different device https://www.youtube.com/watch?v=qWKK_PNHnnA.
Setting up ssh on the Arch iso is the same regardless of which OS your second computer uses.
Install and enable shh on the Arch ISO:
pacman -Sy --needed openssh
systemctl enable sshd.service
To connect you have to find your ip address:
ip address
It will output something like this: The first one is a loop, and it does not have the ip address.
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
This one is ethernet, in this example I am connected to Wi-Fi and ethernet is disabled, so it does not have the ip address. If you are connected with ethernet it will have more things under it like Wi-Fi.
2: enp7s0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel state DOWN group default qlen 1000
link/ether 98:fa:9b:a0:b4:38 brd ff:ff:ff:ff:ff:ff
The third one is Wi-Fi because it starts with wl(wireless lan) The ip address(in brackets) is after inet.
3: wlp0s20f3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 50:e0:85:c4:b6:1b brd ff:ff:ff:ff:ff:ff
inet [192.158.7.113]/24 brd 192.168.8.255 scope global dynamic noprefixroute wlp0s20f3
valid_lft 62454sec preferred_lft 62454sec
inet6 fdd4:62da:c89b:4600:9cae:915f:9bd5:b2e5/64 scope global dynamic noprefixroute
valid_lft 7078sec preferred_lft 3478sec
inet6 fq80::cvfc:3bb6:5994:36c4/64 scope link noprefixroute
valid_lft forever preferred_lft forever
Also set a password on the Arch ISO, it is needed to be able to connect.
passwd
Partitioning
The partition layout:
|EFI system partition (FAT32) | Label=EFI | /dev/your_drive1 | Suggested size is 512 MiB
Mountpoint: /boot/efi
Btrfs root partition | Label=ROOT | /dev/your_drive2 | Suggested size is 23-32 GiB
Subvolume: @ @log @tmp @pkg @snapshots |@home|
Mountpoint: / /var/log /tmp /var/cache/pacman/pkg /.snapshots |/home|
Opional XFS or ext4 home partition | Label=HOME | /dev/your_drive3 | rest of your free space
Mountpoint: /home
Optional Linux Swap | Label=Swap | /dev/your_drive4 | 2x times bigger than ram
Check what drives are available with lsblk:
lsblk
NAME MAJ:MIN RM SIZE
sda 8:0 1 29.9G
└─sda1 8:1 1 29.9G
your_drive 259:0 0 953.9G
Usually sda or sdb is your usb drive with the Arch ISO. Probably the biggest drive will be your computers hard drive.
You can also find scripts with the most popular system configurations in the install-scripts directory, I don't recommend executing the scripts, the best way is to copy the commands one-by-one incase you need to change something inbetween the commands.
I think the easiest to use partitioner is cfdisk
# cfdisk -z /dev/your_drive
Formatting
# mkfs.vfat -F 32 -n EFI /dev/your_drive1
# mkfs.btrfs -L ROOT /dev/your_drive2
If you have a separate home partition
# mkfs.xfs -L HOME /dev/your_drive3
Or
# mkfs.ext4 -L HOME /dev/your_drive3
If you have swap
# mkswap -L SWAP /dev/your_drive4
Mounting
mount /dev/your_drive2 /mnt
cd /mkt
btrfs sub cr /mnt/@
btrfs sub cr /mnt/@tmp
btrfs sub cr /mnt/@log
btrfs sub cr /mnt/@pkg
btrfs sub cr /mnt/@snapshots
If you have one partition for root and home
btrfs sub cr /mnt/@home
cd..
umount /mnt
mount -o relatime,space_cache=v2,ssd,compress=lzo,subvol=@ /dev/sda2 /mnt
mkdir -p /mnt/{boot/efi,home,var/log,var/cache/pacman/pkg,btrfs,tmp}
mount -o relatime,space_cache=v2,ssd,compress=lzo,subvol=@log /dev/sda2 /mnt/var/log
mount -o relatime,space_cache=v2,ssd,compress=lzo,subvol=@pkg /dev/sda2 /mnt/var/cache/pacman/pkg/
mount -o relatime,space_cache=v2,ssd,compress=lzo,subvol=@tmp /dev/sda2 /mnt/tmp
If you have one partition for root and home
mount -o relatime,space_cache=v2,ssd,compress=lzo,subvol=@home /dev/sda2 /mnt/home
mount -o relatime,space_cache=v2,ssd,compress=lzo,subvolid=5 /dev/sda2 /mnt/btrfs
mount /dev/your_drive1 /mnt/boot/efi/
If you have separate home partition
mount /dev/your_drive3 /mnt/home/
If you have swap
swapon /dev/your_drive4
fstab
In the fstab file you should remove the entry with the root partition with the mount point '/', because the entry that is mounted at /btrfs, is the root partition (this is at least how I understood what unicks.eu said)
You need to remove this entry:
/dev/sda2 UUID=3edd5f74-69b7-4d64-b894-aa9f879ddf01
LABEL=ROOT / btrfs rw,relatime,compress=lzo,ssd,space_cache=v2,subvolid=256,subvol=/@,subvol=@
GRUB
Thes are the commands for installing GRUB used in ALU's tutorial.
pacman --needed -Sy grub efibootmgr
grub-install --target=x86_64-efi --bootloader-id=GRUB --efi-directory=/boot/efi
grub-mkconfig -o /boot/grub/grub.cfg
mkdir /boot/efi/EFI/BOOT
cp /boot/efi/EFI/GRUB/grubx64.efi /boot/efi/EFI/BOOT/BOOTX64.EFI
To guarantee that GRUB boots, create a startup script (/boot/efi/startup.nsh) for GRUB with these contents(you can change the name):
bcf boot add 1 fs0:\EFI\GRUB\grubx64.efi "GRUB bootloader"
exit
You can now reboot.
/tmp cleanup
This section was definitely not copied from https://github.com/egara/arch-btrfs-installation Because of /tmp is another subvolume mounted as a traditional partition on /fstab, temporary files won't be deleted by default when the system boots. This can cause some problems like preventing insync to start normally for example, because it uses a temporary file called insync1000.sock and if this file already exists, it won't run. In order to clean up /tmp directory on every reboot, add this configuration file /etc/tmpfiles.d/tmp.conf with this content:
# Cleaning up /tmp directory everytime system boots
D! /tmp 1777 root root 0
Snapper
I suggest setting snapper up after you have a working system.
Install the required packages for snapper and btrfs:
pacman -S snapper grub-btrfs
Check your btrfs subvolumes:
btrfs sub list /
They should look something like this:
ID 256 gen 810 top level 5 path @
ID 257 gen 781 top level 5 path @tmp
ID 258 gen 810 top level 5 path @log
ID 259 gen 804 top level 5 path @pkg
ID 260 gen 10 top level 5 path @snapshots
ID 264 gen 34 top level 256 path var/lib/portables
ID 265 gen 35 top level 256 path var/lib/machines
Create a snapper config for root:
snapper -c root create-config /
Check your btrfs subvolumes:
btrfs sub list /
Now you have a new subvolume for snapshot but there is a problem because the subvolume is below the root subvolume, if you rollback with this configuration /.snapshots will disappear because it depends on the root subvolume.
ID 256 gen 810 top level 5 path @
ID 257 gen 781 top level 5 path @tmp
ID 258 gen 810 top level 5 path @log
ID 259 gen 804 top level 5 path @pkg
ID 260 gen 10 top level 5 path @snapshots
ID 264 gen 34 top level 256 path var/lib/portables
ID 265 gen 35 top level 256 path var/lib/machines
ID 267 gen 87 top level 257 path /.snapshots
To fix it you have to delete the /.snapshots subvolume and make the /.snapshots directory again
btrfs sub del /.snapshots/
mkdir /.snapshots
Now you have to mount the /.snapshots directory in /etc/fstab
nano -w /etc/fstab
Add this line to /etc/fstab(remember to put your drive instead of the example in the beginning)
/dev/your_drive2 /.snapshots btrfs rw,relatime,compress=lzo,ssd,space_cache=v2,subvol=@snapshots 0 0
Mount /.snapshots:
mount /.snapshots/
Check if you have done it correctly with df -Th, it should look something like this:
df -Th
Filesystem Type Size Used Avail Use% Mounted on
dev devtmpfs 3.9G 0 3.9G 0% /dev
run tmpfs 3.9G 1.5M 3.9G 1% /run
/dev/nvme0n1p2 btrfs 32G 7.4G 25G 24% /
tmpfs tmpfs 3.9G 70M 3.8G 2% /dev/shm
tmpfs tmpfs 4.0M 0 4.0M 0% /sys/fs/cgroup
/dev/nvme0n1p2 btrfs 32G 7.4G 25G 24% /btrfs
/dev/nvme0n1p2 btrfs 32G 7.4G 25G 24% /tmp
/dev/nvme0n1p2 btrfs 32G 7.4G 25G 24% /var/cache/pacman/pkg
/dev/nvme0n1p2 btrfs 32G 7.4G 25G 24% /var/log
/dev/nvme0n1p1 vfat 511M 564K 511M 1% /boot/efi
/dev/nvme0n1p3 xfs 921G 144G 778G 16% /home
tmpfs tmpfs 784M 72K 784M 1% /run/user/1000
/dev/nvme0n1p2 btrfs 32G 7.4G 25G 24% /.snapshots
To enable that snapshots show up in GRUB Enable grub-btrfs.path to refresh the shapshot list
systemctl enable grub-btrfs.path
And enable the snapshot list in the GRUB config
nano /etc/default/grub
Set this option:
GRUB_DISABLE_RECOVERY=false
You can exit, now you only have to regenerate the config
grub-mkconfig -o /boot/grub/grub.cfg
Snapper config
To enable pre-post pacman snapshots install snap-pac
pacman -S snap-pac
To enable boot snapshots enable snapper-boot.timer
systemctl enable snapper-boot.timer
You can also enable hourly snapshots and a limit to the number of shanpshots you want or other options in the snapper config
nano /etc/snapper/configs/root
To enable hourly snapshots and snapshot cleanup, you have to enable cronie
pacman -S --needed cronie
systemctl enable cron.service