My cloud-config file for BurmillaOS (Use custom console, add packages for debian/ubuntu console, setup swap, install latest docker compose/buildx etc.)

cloud-init.yml

#cloud-config
hostname: burmilla
rancher:
  upgrade:
   #url: https://raw.githubusercontent.com/benok/burmilla-os-releases/master/releases.yml
    url: https://raw.githubusercontent.com/burmilla/releases/master/releases.yml
  repositories:
    console:
      url: https://raw.githubusercontent.com/benok/burmilla-os-console/master
  console: debian-testing
  network:
    #dns:
    #  nameservers:
    #  - 1.1.1.1
    #  - 1.0.0.1
    interfaces:
      eth0:
      #  address: 192.168.1.123/24
      #  gateway: 192.168.1.254
        dhcp: true
        mtu: 1500
      #eth1:
      #  address: 192.168.2.1/24
      #  mtu: 1500
      #eth2:
      #  address: 192.168.3.1/24
      #  mtu: 1500
    post_cmds:
    - /var/lib/iptables/rules.sh
  environment:
    TZ: JST-9
  services:
    syslog:
      environment:
        - TZ
    console:
      environment:
        - TZ
    system-cron:
      environment:
        - TZ
  services_include:
    #open-vm-tools: true
    qemu-guest-agent: true
  resize_device: /dev/sda
write_files:
# configure docker's address pool
- path: /etc/docker/daemon.json
  owner: root:root
  content: |
    {
      "default-address-pools":
      [
        { "base":"10.254.0.0/16", "size": 24 }
      ]
    }
# define ip table rules
- container: network
  path: /var/lib/iptables/rules.sh
  owner: root:root
  permissions: "0755"
  content: |
    #!/bin/sh
    #iptables -F
    #iptables -P FORWARD ACCEPT
    #iptables -P OUTPUT ACCEPT
    #iptables -A INPUT -s 127.0.0.1 -j ACCEPT
    #iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
    #iptables -A INPUT -p tcp --dport 22 -j ACCEPT
    #iptables -A INPUT -p tcp -i eth0 --dport 80 -j ACCEPT
    #iptables -A INPUT -p tcp -i eth0 --dport 443 -j ACCEPT
    #iptables -A INPUT -p tcp -i eth0 --dport 992 -j ACCEPT
    #iptables -P INPUT DROP
# ntp config
- container: ntp
  path: /etc/ntp.conf
  owner: root
  permissions: "0644"
  content: |+
    server ntp.nict.jp iburst
    server ntp.jst.mfeed.ad.jp iburst
    server time.google.com iburst
    # Allow only time queries, at a limited rate, sending KoD when in excess.
    # Allow all local queries (IPv4, IPv6)
    restrict default nomodify nopeer noquery limited kod
    restrict 127.0.0.1
    restrict [::1]
# add swap file
- path: /etc/rc.addswap
  owner: root
  permissions: "0755"
  content: |+
    #!/bin/sh
    # add swap (original: https://web.archive.org/web/20170713205503/https://coreos.com/os/docs/latest/adding-swap.html)
    SWAP_PATH=/var/lib/rancher/cache/swap
    SWAP_FILE=swapfile1
    #SWAP_SIZE=4g
    SWAP_SIZE=$(grep 'MemTotal:' /proc/meminfo| awk '{printf("%dm\n", $2/1000*2)}') # RAM size * 2
    SWAPINESS=5
    /bin/rm -rf ${SWAP_PATH}
    /bin/mkdir -p ${SWAP_PATH}
    /bin/touch ${SWAP_PATH}/${SWAP_FILE}
    /bin/bash -c "fallocate -l ${SWAP_SIZE} ${SWAP_PATH}/${SWAP_FILE}"
    /bin/chmod 600 ${SWAP_PATH}/${SWAP_FILE}
    /sbin/mkswap ${SWAP_PATH}/${SWAP_FILE}
    /sbin/sysctl vm.swappiness=${SWAPINESS}
    /sbin/swapon ${SWAP_PATH}/${SWAP_FILE}
# setup console
- path: /etc/rc.runonce
  owner: root
  permissions: "0755"
  content: |+
    #!/bin/sh
    FLAG_FILE=/.done.rc.runonce

    if [ -f ${FLAG_FILE} ]; then
      exit 0
    fi

    set -x

    #
    # basic setup
    #
    MY_UBUNTU_MIRROR=http://ftp.iij.ad.jp/pub/linux/ubuntu/archive
    MY_TIMEZONE=Asia/Tokyo

    #
    # change mirror server to my nearest.
    # (deb.debian.org is served by fastly cdn now, changing mirror is not required)
    #
    SRC=/etc/apt/sources.list
    if [ -f ${SRC} ]; then
      if grep ubuntu ${SRC}>/dev/null; then
        # ubuntu
        sed -i.bk -e "s%http://archive.ubuntu.com/ubuntu/%${MY_UBUNTU_MIRROR}/%" ${SRC}
      else
        # add contrib & non-free
        if grep -v non-free ${SRC} > /dev/null; then
          sed -i.bk -e "s/main/main contrib non-free/" ${SRC}
        fi

        # add testing-security (which is almost empty, but it might help someday. -> https://www.reddit.com/r/debian/comments/hr0aj3/sourcelist_for_debian_testing/)
        if grep testing ${SRC}>/dev/null; then
          grep security.debian.org ${SRC} || echo 'deb http://security.debian.org/debian-security testing-security main contrib non-free' >> ${SRC}
        fi
      fi
    else
      # deb822
      SRC=/etc/apt/sources.list.d/ubuntu.sources
      if [ -f ${SRC} ]; then
        # ubuntu(IIJ)
        sed -i -e "s%http://archive.ubuntu.com/ubuntu/%${MY_UBUNTU_MIRROR}/%" ${SRC}
      else
        SRC=/etc/apt/sources.list.d/debian.sources
        # add contrib & non-free
        if grep -v -e 'Components:.*non-free' ${SRC} > /dev/null; then
          sed -i -e "s/main/main contrib non-free/" ${SRC}
        fi
        # testing-security exists
      fi
    fi

    #
    # set timezone
    #
    ln -sf /usr/share/zoneinfo/${MY_TIMEZONE} /etc/localtime

    # done rc.runonce
    touch ${FLAG_FILE}

    # change motd to run package install script
    if [ -f /etc/motd ]; then
      mv /etc/motd /etc/motd.org
    fi
    echo "******************************************" > /etc/motd
    echo "Please run 'sudo /etc/rc.pkginstall' once." >> /etc/motd
    echo "******************************************" >> /etc/motd
# install docker plugins
- path: /etc/rc.install-docker-plugins
  owner: root
  permissions: "0755"
  content: |+
    #!/bin/sh
    #set -x
    # https://gist.github.com/lukechilds/a83e1d7127b78fef38c2914c4ececc3c
    get_latest_release() {
       curl --silent "https://api.github.com/repos/$1/releases/latest" | # Get latest release from GitHub api
       grep '"tag_name":' |                                            # Get tag line
       sed -E 's/.*"([^"]+)".*/\1/'                                    # Pluck JSON value
    }

    # install docker compose plugin (https://kazuhira-r.hatenablog.com/entry/2022/04/30/002702)
    sudo mkdir -p /usr/local/lib/docker/cli-plugins
    ver=$(get_latest_release docker/compose)
    url=https://github.com/docker/compose/releases/download/$ver/docker-compose-linux-x86_64
    echo "Downloading $url..."
    sudo curl -SL $url -o /usr/local/lib/docker/cli-plugins/docker-compose
    sudo chmod a+x /usr/local/lib/docker/cli-plugins/docker-compose
    # support both "docker compose" and "docker-compose" for backward comatibility
    sudo ln -sf /usr/local/lib/docker/cli-plugins/docker-compose /usr/local/bin/docker-compose

    # install docker buildx
    ver=$(get_latest_release docker/buildx)
    url=https://github.com/docker/buildx/releases/download/$ver/buildx-$ver.linux-amd64
    echo "Downloading $url..."
    sudo curl -SL $url -o /usr/local/lib/docker/cli-plugins/docker-buildx
    sudo chmod a+x /usr/local/lib/docker/cli-plugins/docker-buildx
# install packages
- path: /etc/rc.pkginstall
  owner: root
  permissions: "0755"
  content: |+
    #!/bin/sh
    set -x

    # unminimize on ubuntu
    if [ -f /etc/legal ]; then
      yes | unminimize
    fi

    # upgrade & install packages
    export DEBIAN_FRONTEND=noninteractive
    apt-get update
    apt-get full-upgrade -y -o DPkg::options::="--force-confdef" -o DPkg::options::="--force-confold"
    apt-get autoremove -y
    apt-get install -y \
      haveged \
      tzdata \
      \
      zsh \
      screen \
      \
      vim \
      git \
      jq \
      \
      unzip \
      zstd \
      pv \
      \
      inetutils-traceroute \
      dnsutils \
      nfs-common \
      bridge-utils \
      netcat-openbsd \
      lsof \
      \
      rclone \
      fuse3 \
      \
      golang \
      \
      python3-pip \
      dialog \
      man-db

    unset DEBIAN_FRONTEND

    #sudo pip3 install -I pip
    #sudo pip install pip-autoremove
    #sudo pip install docker-compose

    # install docker-compose, buildx
    /etc/rc.install-docker-plugins

    # set python3 default
    if [ -x /usr/bin/python2 ]; then
      update-alternatives --install /usr/bin/python python /usr/bin/python3 1
      update-alternatives --install /usr/bin/python python /usr/bin/python2 2
      update-alternatives --set python /usr/bin/python3
    fi

    # chsh to zsh
    if [ -x /bin/zsh ]; then
      chsh -s /bin/zsh rancher
    fi

    # symlink user_config.yml
    ln -sf /var/lib/rancher/conf/cloud-config.d/user_config.yml /home/rancher/user_config.yml

    # update motd
    if [ -f /etc/motd.org ]; then
      # debian
      mv /etc/motd.org /etc/motd
    else
      # ubuntu
      rm -f /etc/motd
    fi

    if [ -f /etc/update-motd.d/10-help-text ]; then
      rm /etc/update-motd.d/10-help-text
    fi

    set +x
    echo '###########################'
    echo '# package install finished.'
    echo '###########################'
# use IPv4 for apt
- path: /etc/apt/apt.conf.d/99force-ipv4
  owner: root
  permissions: "0644"
  content: |+
    Acquire::ForceIPv4 "true";
runcmd:
  # separate cloud specific script to /opt
  - '[ -x /opt/rc.oem ] && /opt/rc.oem'
  - /etc/rc.addswap
  - /etc/rc.runonce
  # always try to resizefs on boot
  - rm /var/lib/burmilla/resizefs.done
  # generate /etc/lsb-release for burmilla OS
  - /etc/init.d/generate-lsb-release start
  # Adding entropy is quite important for cloud, vps, VMs. (e.g. Prevent from intermittent docker command stalling)
  - /etc/init.d/haveged start
  #- sed -i.bak 's/^.*\(AllowTcpForwarding\).*/    \1 yes/' /etc/ssh/sshd_config
ssh_authorized_keys:
  # https://github.com/benok.keys (Never use the line below. use https://github.com/<<YOUR_ACCOUNT>>.keys)
  - ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIKW3eVCs/HnGgUEBOxTPDWlvblEsZhlIB6Yn1elpPqXX