manual_installation.sh

#!/bin/bash

# Installation based on https://wiki.archlinux.org/title/Installation_guide

# 1. Pre-installation

download_and_verify_iso() {
    echo "****************************************"
    echo "*** 1.1 Aquire an installation image ***"
    echo "****************************************"
    curl -s -o arch_checksums.html https://archlinux.org/download/#checksums
    ARCH_RELEASE=$(cat arch_checksums.html | grep -oP 'Current Release:.*?\K[0-9.]+')
    ISO_CHECKSUM=$(cat arch_checksums.html | grep -oP 'SHA256:.*?\K([0-9a-fA-F]{64})')
    ISO_FILENAME="archlinux-${ARCH_RELEASE}-x86_64.iso"
    ISO_DL_PATH="https://ftp.lysator.liu.se/pub/archlinux/iso/${ARCH_RELEASE}/${ISO_FILENAME}"
    rm arch_checksums.html
    wget -q -c --show-progress -O "$ISO_FILENAME" "$ISO_DL_PATH"
    echo "Download complete..."

    echo ""
    echo "****************************"
    echo "*** 1.2 Verify signature ***"
    echo "****************************"
    DOWNLOADED_ISO_CHECKSUM=$(sha256sum "${ISO_FILENAME}" | awk '{print $1}')
    echo "Wanted SHA256 Checksum: $ISO_CHECKSUM"
    echo "Actual SHA256 Checksum: $DOWNLOADED_ISO_CHECKSUM"
    [ "$ISO_CHECKSUM" != "$DOWNLOADED_ISO_CHECKSUM" ] && \
    { echo "Checksum error on downloaded ISO. Rerun the script..."; exit 1; }
    echo "Checksum is OK..."
}

write_iso() {
    echo ""
    echo "******************************************"
    echo "*** 1.3 Prepare an installation medium ***"
    echo "******************************************"
    echo "Partitions:"
    sudo parted -l | grep "Disk /"
    echo ""
    echo "Run the following command with the correct value for 'of='"
    echo ""
    echo "sudo dd if=${ISO_FILENAME} of=/dev/sdX bs=4M status=progress && sync"
}

main() {
    echo "**********************************************"
    echo "* Arch Linux Installation - Pre-installation *"
    echo "**********************************************"
    echo ""
    download_and_verify_iso
    write_iso
    exit
}

main