feat: Persistant MAC address (#445)

  fi

  if [ -z "$MAC" ]; then

    local file="$STORAGE/$PROCESS.mac"

    if [ -f "$file" ]; then

      MAC=$(<"$file")

    else

      # Generate MAC address based on Docker container ID in hostname

      MAC=$(echo "$HOST" | md5sum | sed 's/^\(..\)\(..\)\(..\)\(..\)\(..\).*$/02:\1:\2:\3:\4:\5/')

      echo "${MAC^^}" > "$file"

    fi

  fi

  VM_NET_MAC="${MAC^^}"