Arch on external disk

On this installation I will install Arch Linux with LXDE on a flash drive from a working Arch setup

The first step is to install the Arch install related stuff.

sudo pacman -S arch-install-scripts

Disks

Verify the drive you want to partition

lsblk

Then part it

fdisk /dev/sdx

In here I will create a new empty DOS partitoin table and make two partitions
A 128Mb partition for boot and the rest for root

The boot partition needs to have the bootable flag

Format boot

mkfs.ext4 /dev/sdx1

Then root

mkfs.ext4 /dev/sdx2

Now for the swapfile

mkswap -U clear --size 4G --file /swapfile

Now mounting the things

Mount root

mount /dev/sdx2 /mnt

Create directoy for boot

mkdir /mnt/boot

mount boot

mount /dev/sdx1 /boot

Activate the swap

swapon /swapfile

Generate the fstab

genfstab -U /mnt >> /mnt/etc/fstab

Install the bare minimum

pacstrap /mnt base base-devel linux linux-firmware vim linux-headers

And move to the system

arch-chroot /mnt

For the timezone

ln -sf /usr/share/zoneinfo/Portugal /etc/localtime

Syncing the hardware clock

hwclock --systohc

Find the language/locale that you want and uncomment that

vim /etc/locale.gen

Now you need to regenerate the locales

locale-gen

Add the language you want

vim /etc/locale.conf

And write something like this.

LANG=en_US.UTF-8

To define the keyboard layout

vim /etc/vconsole.conf

KEYMAP=pt-latin9

Set the name for your machine

vim /etc/hostname

Edit the hosts

vim /etc/hosts

Write

127.0.0.1     localhost  
::1           localhost  
127.0.1.1     host_name.localdomain host_name

Replace host_name with the name you wrote on /etc/hostname

Define root password

passwd

Add a regular user

useradd -m -nome_utilizador  
passwd -nome_utilizador

Make it a root user

usermod -aG wheel -nome_utilizador

EDITOR=vim visudo

In the file uncomment the wheel option

pacman -S grub efibootmgr  
grub-install --target=x86_64-efi --efi-directory=/boot/ --bootloader-id=GRUB  
grub-mkconfig -o /boot/grub/grub.cfg

Must say Found linux image and Found initrd image. If it doesn't then the kernel isn't installed.

pacman -S lxde

exit

umount /dev/sdx1

umount /dev/sdx2

Now you need to put the disk on the main machine boot from a USB drive
You can get the ISO image here and burn it to the drive like so:

umount /dev/sdx1  
sudo dd if=~/Downloads/archlinux-20xx.xx.xx-x86_64.iso of=/dev/sdx conv=fdatasync status=progress

Now you need to remount everything and chroot

mount /dev/sdx2 /mnt  
mount /dev/sdx1 /boot  
swapon /swapfile  
arch-chroot /mnt

And now you need to reinstall grub

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

Must say Found linux image and Found initrd image. If it doesn't then the kernel isn't installed.

And now it should be done.

exit  
umount /dev/sdx1  
umount /dev/sdx2  
poweroff

Remove the flash drive and turn on the computer. Everything should work.