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Provision workers with QEMU ​

QEMU is an open source virtualization tool, which allows you to launch VMs on many different architectures. Using QEMU together with meltcloud is handy to quickly get a node joined to your meltcloud clusters.

Prerequisites ​

  1. Create an iPXE Boot Artifact or reuse an existing one
  2. Download the ipxe.iso file used to launch the QEMU virtual machine.

Launch a Virtual Machine with QEMU ​

Directly launch a virtual machine using QEMU and the previously generated ipxe.iso boot image.

shell
# install QEMU
brew install qemu

# setup a path to store your QEMU VM files
disk_path=$HOME/qemu/melt-vm
mkdir -p ${disk_path}

# create a disk for the ephemeral root device that holds docker images
qemu-img create -f qcow2 ${disk_path}/melt-node.qcow2 10g

# iPXE ISO path - adjust if needed
ipxe_iso="$HOME/Downloads/ipxe.iso"

# assign a UUID - be aware that creating a new UUID will create a new machine in meltcloud
machine_uuid=$(uuidgen)

mem=3G # requires at least 3GB - give more for more workload
cpus=6 # no minimum requirement for CPU, but let's give it some power!

# start the machine (Ctrl-a, release, hit x to exit)
qemu-system-aarch64 \
  -uuid $machine_uuid \
  -m $mem \
  -smp $cpus \
  -device nec-usb-xhci,id=usb-bus \
  -device usb-storage,drive=ipxe-iso,removable=true,bootindex=0,bus=usb-bus.0 \
  -drive if=none,id=ipxe-iso,media=cdrom,file=${ipxe_iso},readonly=on \
  -drive file=$(brew --prefix qemu)/share/qemu/edk2-aarch64-code.fd,if=pflash,format=raw \
  -drive file=${disk_path}/melt-node.qcow2,if=virtio \
  -netdev user,id=n1 \
  -device virtio-net-pci,netdev=n1,bus=pcie.0,addr=0x19 \
  -nographic \
  -cpu host \
  -machine type=virt-9.0,accel=hvf
shell
# install QEMU
sudo apt install qemu-system libvirt-clients libvirt-daemon-system
sudo adduser `id -un` libvirt
sudo adduser `id -un` kvm

# create a disk for the ephemeral root device
DISK_PATH=~/melt-node.qcow2
qemu-img create -f qcow2 $DISK_PATH 10g

# give QEMU access to the disk file
sudo chown libvirt-qemu:kvm "$DISK_PATH"
pushd $(dirname $DISK_PATH)
setfacl -m user:libvirt-qemu:--x $(pwd)
while [[ $(pwd) != $HOME ]]; do
  cd ..
  pwd
  setfacl -m user:libvirt-qemu:--x $(pwd)
done
popd

# iPXE ISO path (Download from meltcloud foundry)
IPXE_ISO=~/Downloads/ipxe.iso

# assign a UUID - be aware that creating a new UUID will create a new machine in meltcloud
machine_uuid=$(uuidgen)

# start the machine (To exit press Alt + 2, then type "quit")
sudo qemu-system-x86_64 \
  -uuid $machine_uuid \
  -m size=3276800k \
  -accel kvm \
  -smp 2,sockets=2,cores=1,threads=1 \
  -object '{"qom-type":"memory-backend-ram","id":"pc.ram","size":3355443200}' \
  -machine pc-i440fx-mantic,usb=off,vmport=off,dump-guest-core=off,memory-backend=pc.ram,hpet=off,acpi=on \
  -cdrom $IPXE_ISO \
  -display curses \
  -cpu host \
  -netdev user,id=hostnet0 \
  -device e1000,netdev=hostnet0,bus=pci.0,addr=0x3 \
  -drive file=$DISK_PATH,if=virtio \
  -boot order=d