qemu-cloudrun.sh

#!/usr/bin/env bash

cpucores="2"
ram="2G"
disk="30G"
username="vm"
password="111111"
vm_name="VM1"
ver="22.04"
img="ubuntu-${ver}-server-cloudimg-amd64.img"
qcow="ubuntu-${ver}.qcow2"
cloud_init_cfg="cloud-init.yaml"
cloud_init_iso="cloud-init.iso"
port_mapping=(
"2222-:22"
"3333-:3306"
"4443-:443"
"3003-:3003"
"3128-:3128"
"1500-:500"
"4500-:4500"
"1701-:1701"
"1194-:1194"
)


# sudo apt-get install cloud-image-utils qemu libguestfs-tools

if [ ! -f "$img" ] && [ ! -f "$qcow" ]; then
  wget "https://cloud-images.ubuntu.com/releases/${ver}/release/${img}"
fi

if [ ! -f "$qcow" ]; then
  # This is already in qcow2 format.
  # sparse resize: does not use any extra space, just allows the resize to happen later on.
  # https://superuser.com/questions/1022019/how-to-increase-size-of-an-ubuntu-cloud-image
  qemu-img resize $img $disk
  echo "Installing ..."
  qemu-img convert -f qcow2 -O qcow2 $img $qcow
  # rm $img
fi

if [ ! -f "$cloud_init_iso" ]; then
# For the password.
cat >$cloud_init_cfg <<EOF
#cloud-config
system_info:
  default_user:
    # name: ${username}
    name: root
    # home: /home/${username}
    home: /root

password: ${password}
chpasswd: { expire: False }
hostname: ${vm_name}

# configure sshd to allow users logging in using password
# rather than just keys
ssh_pwauth: True
ssh_deletekeys: false
disable_root: false

runcmd:
  - sed -i 's/#PermitRootLogin prohibit-password/PermitRootLogin yes/' /etc/ssh/sshd_config
  - service ssh restart
EOF
  cloud-localds $cloud_init_iso $cloud_init_cfg
fi


netid="rtl8139,netdev=net0"
netdev="user,id=net0"
for i in "${port_mapping[@]}"; do
   netdev="$netdev,hostfwd=tcp::$i"
done

qemu-system-x86_64 \
  -drive "file=${qcow},format=qcow2" \
  -drive "file=${cloud_init_iso},format=raw" \
  -device $netid \
  -smp $cpucores \
  -m $ram \
  -netdev $netdev \
  -serial mon:stdio \
  -vga virtio \
  -enable-kvm \
  -nographic