Simple script to install Debian on a variety of architectures with QEMU

easy-debian-qemu.sh

#!/bin/bash

# The architecture you want to install. Options:
# amd64 arm64 armel armhf i386 mips64el mipsel ppc64el s390x
arch=armhf
disk=16G
cores=2
RAM=4G

# Determine the correct QEMU platform based on the value of $arch
case $arch in
  amd64)             platform=x86_64 ;;
  arm64)             platform=aarch64 ;;
  armel | armhf)     platform=arm ;;
  i386)              platform=i386 ;;
  mips64el | mipsel) platform=mips ;;
  ppc64el)           platform=ppc ;;
  s390x)             platform=s390x ;;
esac

# Install the right QEMU platform binaries and QEMU utils so we can mount qcow images
apt-get install qemu-system-$platform qemu-utils

# Download the kernel, initrd, and netboot ISO
wget -O initrd-$arch.gz http://ftp.debian.org/debian/dists/stable/main/installer-$arch/current/images/netboot/initrd.gz &
wget -O vmlinuz--$arch.gz http://ftp.debian.org/debian/dists/stable/main/installer-$arch/current/images/netboot/vmlinuz &
wget -O mini-$arch.iso http://ftp.debian.org/debian/dists/stable/main/installer-$arch/current/images/netboot/mini.iso

# Create a raw disk
qemu-img create -f qcow2 debian-$arch.qcow2 $disk

# Boot and install the OS. Node that GRUB will fail to install (that's expected)
qemu-system-$platform -M virt -cpu max -smp cores=$cores -m $RAM -serial stdio \
    -kernel vmlinuz-$arch -initrd initrd-$arch.gz \
    -drive file=mini-$arch.iso,if=none,id=cd,media=cdrom,read-only -device virtio-blk-device,drive=cd \
    -drive file=debian-$arch.qcow2,if=none,id=hd -device virtio-blk-device,drive=hd \
    -device virtio-net-device,netdev=net0 -netdev user,id=net0

# Mount the disk image to copy off the boot kernel and initrd
modprobe nbd max_part=8
qemu-nbd --connect=/dev/nbd0 debian-$arch.qcow2
mount /dev/nbd0p1 /mnt/
cp /mnt/* boot-$arch/ -rv

# Remove the ISO and change the kernel and initrd to what was copied using the above commands
qemu-system-$platform -M virt -cpu max -smp cores=$cores -m $RAM -nographic \
    -kernel ./boot-$arch/vmlinuz -initrd ./boot-$arch/initrd.img -append "root=/dev/vda2" \
    -drive file=debian-$arch.qcow2,if=none,id=hd -device virtio-blk-device,drive=hd \
    -device virtio-net-device,netdev=net0 -netdev user,id=net0,hostfwd=tcp::5022-:22 &
    # Add `-serial stdio` to params and `console=ttyAMA0` to `-append` kernel args to redirect guest's console to localhost