#refresh 0 https://ubuntu.com/server/docs/boot-arm64-virtual-machines-on-qemu

Ubuntu/arm64 can run inside the QEMU emulator. You can either do this fully emulated (e.g. on an x86 host) or, accelerated w/ KVM if you have an arm64 host. This page describes how to do both.

I've chosen to describe a UEFI-based system here so I can make use of the kernel on the guest's disk image. It is possible to boot directly into Linux instead.

'''Note: this requires Ubuntu 20.04 or greater'''
= Getting the bits =
 1. Install QEMU and the EFI image for QEMU:
 {{{
 $ sudo apt-get install qemu-system-arm qemu-efi
 }}}
 1.Create a VM-specific flash volume for storing NVRAM variables:
 {{{
 $ cp /usr/share/AAVMF/AAVMF_CODE.fd flash1.img
 }}}
 1. Now you should be able to boot/ into a ''-arm64.img'' type [[http://cloud-images.ubuntu.com|cloud image]].
  a. For accelerated VMs (arm64 host w/ KVM support)
  {{{
  $ sudo qemu-system-aarch64 -enable-kvm -m 1024 -cpu host -M virt -nographic -pflash /usr/share/AAVMF/AAVMF_CODE.fd -pflash flash1.img -drive if=none,file=jammy-server-cloudimg-arm64.img,id=hd0 -device virtio-blk-device,drive=hd0 -netdev type=tap,id=net0 -device virtio-net-device,netdev=net0,mac=$randmac
  }}}
  '''Note: For GICv3 systems, such as Cavium ThunderX, you must use QEMU from Ubuntu 16.04 or newer, and pass "-M virt,gic-version=3". Additionally, you must use a 15.10 (wily) or newer cloud image for guests.'''

  a. For emulated VMs (e.g. x86 host)
  {{{
  $ sudo qemu-system-aarch64 -m 1024 -cpu cortex-a57 -M virt -nographic -pflash /usr/share/AAVMF/AAVMF_CODE.fd -pflash flash1.img -drive if=none,file=jammy-server-cloudimg-arm64.img,id=hd0 -device virtio-blk-device,drive=hd0 -netdev type=tap,id=net0 -device virtio-net-device,netdev=net0,mac=$randmac
  }}}

= Troubleshooting =
== Generate MAC Address ==
In the above command, we use ''randmac'' as a variable of mac address. You may generate it by the following command:

  {{{
  #!/usr/bin/python3

  import random

  def randomMAC():
      return [ 0x00, 0x16, 0x3e,
               random.randint(0x00, 0x7f),
               random.randint(0x00, 0xff),
               random.randint(0x00, 0xff) ]

  def MACprettyprint(mac):
      return ':'.join(map(lambda x: "%02x" % x, mac))

  if __name__ == '__main__':
      print(MACprettyprint(randomMAC()))
  }}}

== No Output and No Response ==
If such thing happens to you, align your host and guest release version may help. For example, if you generated ''flash0.img'' on Focal but want to emulate Jammy with the cloud image of Jammy, the firmware is not fully compatible. Generating ''flash0.img'' on Jammy when emulating Jammy with the cloud image of Jammy may help.

= References =
 * https://wiki.linaro.org/LEG/UEFIforQEMU
 * http://blog.eciton.net/uefi