Creating a MicroVM with QEMU

Lightweight Alpine Linux VM on MacOS

Jun 15, 2024ยท

3 min read

Virtualization is a powerful technology that allows you to run multiple operating systems on a single host system. QEMU, an open-source emulator, is an excellent tool for creating virtual machines on macOS. In this guide, we will walk you through the process of preparing an Alpine Linux image and booting it up using QEMU on your macOS system. Alpine Linux is known for its lightweight nature and security, making it an ideal choice for virtualization

Prerequisites:

  • Prior to beginning, please verify that you have already installed QEMU on your system. You can refer to the following tutorial for guidance: Getting Started with QEMU: Your Gateway to Virtual Machines.

  • Additionally, ensure you have downloaded an Alpine Linux ISO file to your system.
    You can download it from here.

  • You will also need to download the QEMU_EFI image, which can be obtained from this link.

Steps to Prepare the Alpine Linux Image and Boot the VM:

  1. Create Disk Images:

    Before you can boot the Alpine Linux VM, you need to create a disk image to install the operating system. Use the following command to create a 5GB disk image file named alpine.qcow2:

     $ qemu-img create -f qcow2 alpine.img 5G
    

    Additionally, you'll want to create a variable storage disk image named varstore.img. This 64MB virtual disk acts as dedicated storage for temporary data and configurations used by your Alpine Linux virtual machine. In order to create vartstore.img you need to follow this command:

     $ qemu-img create -f qcow2 varstore.img 64M
    
  2. Start the Alpine Linux Installation:
    Use the following command to start the Alpine Linux installation:

     $ qemu-system-aarch64 -m 1024 \
       -drive if=pflash,format=raw,file=QEMU_EFI.img \
       -drive if=pflash,file=varstore.img \
       -drive if=virtio,file=alpine.img \
       -cdrom alpine-linux.iso -boot d -netdev user,id=eth0 \
       -device virtio-net-pci,netdev=eth0
    
    • -m 1024 specifies the VM's memory size (1GB).

    • -drive if=pflash,format=raw,file=QEMU_EFI.img line refers to the pflash disk image for EFI firmware.

    • -drive if=pflash,file=varstore.img line designates the variable storage disk image.

    • -drive if=virtio,file=alpine.img is for the main Alpine Linux disk image.

    • -cdrom alpine-linux.iso mounts the Alpine Linux ISO as a CD-ROM.

    • -boot d specifies to boot from the CD-ROM.

    • -netdev user,id=eth0 -device virtio-net-pci,netdev=eth0 configures a user-mode network connection.

  3. Install Alpine Linux:
    Follow the on-screen instructions to install Alpine Linux on the virtual machine. You can choose to install it on the virtual disk you created (/dev/vda).

  4. Boot the VM:

    Once the installation is complete, shut down the VM using ^ + d, and then boot the VM with your newly installed Alpine Linux using the following command:

     qemu-system-aarch64 -m 4G -nographic \
     -drive if=pflash,format=raw,file=QEMU_EFI.img \
     -drive if=pflash,file=varstore.img \
     -drive if=virtio,file=alpine.img \
     -netdev user,id=eth0,hostfwd=tcp::2222-:22 \
     -device virtio-net-pci,netdev=eth0
    

    Your Alpine Linux VM is now up and running.

Conclusion:

You've successfully prepared an Alpine Linux image and booted it up on your macOS system using QEMU. This lightweight and secure Linux distribution is ideal for various virtualization tasks. Explore Alpine Linux's package management system, build custom VMs, and enjoy the flexibility and performance that QEMU offers for virtualization on macOS.