ubuntu cloud image creation

ubuntu cloud image creation

How to create a simple cloud image 

sudo apt-get install cloud-utils
wget https://cloud-images.ubuntu.com/xenial/current/xenial-server-cloudimg-amd64-disk1.img
mv xenial-server-cloudimg-amd64-disk1.img xenial-server-cloudimg-amd64-disk1.img.dist
qemu-img convert -O qcow2 xenial-server-cloudimg-amd64-disk1.img.dist xenial-server-cloudimg-amd64-disk1.img
qemu-img resize xenial-server-cloudimg-amd64-disk1.img +40G

user-data
#cloud-config
users:
  - name: demo
    ssh-authorized-keys:
      - ssh-rsa xxx
      - ssh-rsa yyy
    sudo: ['ALL=(ALL) NOPASSWD:ALL']
    groups: sudo
    shell: /bin/bash
runcmd:
  - sed -i -e '$aAllowUsers demo' /etc/ssh/sshd_config
  - restart ssh

cloud-localds user-data.img user-data

#Create your own macvtap device with a random mac
sudo ip link del "$MACVTAP"
sudo ip link add link "$PDEV" name "$MACVTAP" type macvtap mode bridge
sudo ip link set "$MACVTAP" address 02:00:DE:AD:02:01 up
sudo ip link show "$MACVTAP"

if [ ! -f "$IMAGE" ]; then
        >&2 echo "Can't find image file \"$IMAGE\""
        exit 1
fi
rm -f debug.log

tapindex=$(< /sys/class/net/"$MACVTAP"/ifindex)
tapdev=/dev/tap"$tapindex"

ifconfig "$MACVTAP" up

qemu-system-x86_64 \
        -enable-kvm \
        -smp cpus=4,cores=2 -cpu host \
        -vga none -nographic \
        -drive file="$IMAGE",if=virtio,aio=threads \
        -net nic,model=virtio,macaddr=$(< /sys/class/net/"$MACVTAP"/address) -net tap,fd=3 3<>"$tapdev" \
        -drive file=user-data.img,if=virtio,media=cdrom \
        -debugcon file:debug.log -global isa-debugcon.iobase=0x402