NoSuchPortException, ttyUSB0 not accessible for dialout group

Hi I’m a newbie on linux and trying to get my rolling shutters controlled using openHAB on my Synology NAS with the RFXCom transceiver connected to it.

Running openHAB on Synology NAS DSM 6.2.1-23824 Update 4 and trying to get my RFXCom connected but keep getting error: Connection to RFXCOM transceiver failed null

I added the daemon user openhab to dialout group

Running command ls -l /dev/ttyUSB*
I get:
crw-rw---- 1 root root 188, 0 Jan 3 01:22 /dev/ttyUSB0

I believe the problem is that ttyUSB0 is only accessible for root-users. On a Synology NAS, what is the right approach to get user openhab access ttyUSB0 and how to achieve this?

Change owner of /dev/ttyUSB0 from root root to root dialout.

@H102, thanks, how can I do this?

Use something like sudo chown root:dialout /dev/ttyUSB0

See here for more info on how to use chown

If you’re changing both user and group, use “.” or “:” in between.

root.dialout / root:dialout
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@gitMiguel thanks for catching my typo.:+1: I edited my post to add the missing :

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Sorry have been away for quite a while
Thanks @H102, this command seems to work.
However I’m using symlink to keep my USB device fixed.
Using the command on the symlink however doesn’t do much good as the changes get applied to /dev/ttyUSB0 and not the symlink /dev/ttyUSB-RFX433E
Can’t seem to find the right command to do this, or am I barking up the wrong tree?

Ah, adding -h seems to do the trick

Glad you got it solved, thanks for adding what was needed for your setup to work.!

For others that may not be familiar with linux, and how user/group can be changed, here’s link that hopefully you find useful.