Arch Linux - Btrfs Installation (Dual Boot)

Mounting the root partition

To mount the root partition, issue the command:

mount /dev/nvme0n1p8 /mnt

Creating and mounting btrfs subvolumes

Since we’ve mounted the root partition, we can proceed into creating btrfs subvolumes.
We’ll create 6 different subvolumes:

• @ => root directory.
• @home => home directory. Contains all your personal data.
• @var => var directory. Contains logs, etc.
• @opt => opt directory. Contains third party products.
• @tmp => tmp directory. Contains temp files, etc.
• @.snapshot => snapshot directory. Contains btrfs snapshots. (Can be excluded if you want to use Timeshift)

Create the subvolumes:

btrfs su cr /mnt/@
btrfs su cr /mnt/@home
btrfs su cr /mnt/@var
btrfs su cr /mnt/@opt
btrfs su cr /mnt/@tmp
btrfs su cr /mnt/@.snapshots
umount /mnt

Now to mount them:

mount -o noatime,commit=120,compress-force=zstd:7,discard=async,space_cache,subvol=@ /dev/nvme0n1p8 /mnt
mkdir /mnt/{boot,home,var,opt,tmp,.snapshots} # You must create the folders before proceeding
mount -o noatime,commit=120,compress-force=zstd:7,discard=async,space_cache,subvol=@home /dev/nvme0n1p8 /mnt/home
mount -o noatime,commit=120,compress-force=zstd:7,discard=async,space_cache,subvol=@tmp /dev/nvme0n1p8 /mnt/tmp
mount -o noatime,commit=120,compress-force=zstd:7,discard=async,space_cache,subvol=@opt /dev/nvme0n1p8 /mnt/opt
mount -o noatime,commit=120,compress-force=zstd:7,discard=async,space_cache,subvol=@.snapshots /dev/nvme0n1p8 /mnt/.snapshots
mount -o discard=async,subvol=@var /dev/nvme0n1p8 /mnt/var

A little review about the options:

• noatime: No access time. Improves performance by not writing time when the file was accessed.
• commit: Perodic interval (in seconds) in which data is synchronized to permanent storage.
• compress-force: Activating forced compression and choosing the algorithm for compression. (Believe me, this is good, no joke)
• discard=async: Frees unused block from an SSD drive supporting the command. With discard=async, freed extents are not discarded immediately, but grouped together and trimmed later by a separate worker thread, improving commit latency. You can opt out of this if you use HDD.
• space_cache: Enables kernel to know where block of free space is on a disk to enable it to write data immediately after file creation.
• subvol: Choosing the subvolume to mount.

Mounting the EFI (boot) partition

To mount it, just issue:

mount /dev/nvme0n1p6 /mnt/boot

Verify if you are doing it correctly

To check what is being mounted, issue:

lsblk

Setting up timezone

Before you set up timezone, you might want to check which timezones are available by issuing:

timedatectl list-timezones

Press ‘q’ to quit the list.

Now set up your timezone by using:

ln -sf /usr/share/zoneinfo/Region/City /etc/localtime

Sync hardware and system clock

Issue this command:

hwclock --systohc

Generating system locale

Issue this command to edit the locale.gen:

nano /etc/locale.gen

Scroll and uncomment your language. Most people would prefer US English so scroll down and uncomment this line:

en_US.UTF-8 UTF8

Save the file by using CTRL + S and exit it with CTRL + X.

Now generate locale:

locale-gen

Set the locale in locale.conf file:

echo LANG=en_US.UTF-8 >> /etc/locale.conf

Change en_US.UTF-8 to your preferred language (if true).

Setting keymap

Note: This is only if you use keymaps other than the standard QWERTY.

echo KEYMAP=[keymap] >> /etc/vconsole.conf

Replace [keymap] with the ones you choose before.

Setting network configuration

Set your hostname with:

echo example >> /etc/hostname

Replace the example with anything you want.

Now for the hostfile:

nano /etc/hosts

Reffering to Arch Wiki, the format should look like this:

127.0.0.1   localhost
::1         localhost
127.0.1.1   example.localdomain example

Save the file by using CTRL + S and exit it with CTRL + X.

Setting up the root user

Set up password for the root user with:

passwd

Note: Visual feedbacks are disabled by default in Linux because of security reasons.

Installing remaining essentials

pacman -S grub grub-btrfs efibootmgr base-devel linux-headers networkmanager network-manager-applet wpa_supplicant dialog os-prober mtools dosfstools reflector git

These are some basic sets of packages you will need if you plan to use Arch in the long run. I would recommend that you google all packages to understand what they do. After entering the command, press Enter to select all of the base-devel packages to install. Then wait for the installation to finish.

Modifying mkinitcpio

nano /etc/mkinitcpio.conf

Add btrfs into MODULES so that it looks like:

...
MODULES=(btrfs)
...

Save the file by using CTRL + S and exit it with CTRL + X.

Installing GRUB

To install GRUB into the /boot partition, issue these commands:

grub-install --target=x86_64-efi --efi-directory=/boot --bootloader-id=Arch
grub-mkconfig -o /boot/grub/grub.cfg

Creating a user

Issue this command to create a new user:

useradd -mG wheel example

Above command creates a user with name example and adds the user to the wheel group (for sudo privileges). Replace example with whatever name you want.

Then create the password for the user:

passwd example

Giving user sudo permission

EDITOR=nano visudo

Uncomment the line %wheel ALL=(ALL) ALL

Enabling NetworkManager

systemctl enable NetworkManager.service