Synology USB Devices

Hi All,
finally I solved the problem of the USB devices (like Z-Wawe sticks) on Synology platform
I found lot of articles and lot of solutions, so I decided to make a definitive guide:


  1. Permsssion : Synology install tty devices with root permission and openHab connot use them
  2. Name: the name of the device is changed every time so you can have ttyUSB0 or ttyUSB1, etc with the necessity to modify the controller configuration every time the USB i reinserted or the server rebooted

to solve the problem the key is udev and its magic!

  1. ssh in the Synology
  2. cd /lib/udev/rules.d (where udev rules are stored)
  3. sudo vi 99-openhab.rules (create a new rule .rules is mandatory)
  4. in the new file enter this two rules:
    4.1 DRIVERS==“cp210x”, ATTRS{interface}==“Standard Com Port”, SYMLINK+=“ttyUSB4”,OWNER:=“openhab”,GROUP:=“users”, MODE:=“0666”
    4.2 DRIVERS==“cp210x”, ATTRS{interface}==“HubZ Z-Wave Com Port”, SYMLINK+=“ttyUSB3”,OWNER:=“openhab”,GROUP:=“users”, MODE:=“0666”

DRIVER and ATTRS are used to identify the device to map, you can check your device information using the udevadm info -a /dev/ttyUSB0 on the device to map to find the correct rules

the key point is to use as a SYNLINK a ttyUSBx name because if you use a dfferent one, openHab do not include it in the list of available ports. I found lot of article on haw to add a new name to the list, but I was unable to find the right place to add the setting in synology

  1. sudo udevadm control --reload
  2. disconnect and riconnect the device
  3. check the results ls -la /dev, you sould find the original USB port whit openhab:user and two synlink to ttyUSB3 and ttyUSB4.
  4. in the controller configuration you will find the new ttyUSB3 and ttyUSB4 ports.

Every Synology update you need to recreate the 99-openhab.rules file, so keep a copy somewhere!

Hope this helps some one!