buster64 on x86_64

Workaround

Vagrant.configure("2") do |config|
  config.vm.box = "debian/buster64"
  config.vm.synced_folder ".", "/vagrant", disabled: true
  config.vm.provider "qemu" do |qe|
    qe.qemu_dir = "/usr/bin/"
    qe.arch="x86_64"

    # need for x86_64
    qe.machine = "q35"
    qe.cpu = "max"
    qe.net_device = "virtio-net-pci"

    # it seems this box need a VGA device (the debug serial port doesn't work... I don't know why)
    qe.extra_qemu_args = %w(-vga std)
  end
end

Try to fix the box

This may caused by the serial console is disabled. Following steps may fix it (tested on debian10):

1. up the VM with '-vga std'
2. ssh to it, and enable serial console by edit /etc/default/grub
   1. add console=tty0 console=ttyS0 to GRUB_CMDLINE_LINUX
   2. add

      GRUB_TERMINAL="serial console"
      GRUB_SERIAL_COMMAND="serial"
      

   3. update grub by update-grub -o /boot/grub/grub.cfg
3. stop the VM
4. then you can drop the '-vga std' in the Vagrantfile