I’m having some problems with the access rights of USB-to-serial converters in 16.0. They show up nicely as /dev/ttyUSB0 and /dev/ttyUSB1, but they are owned by root and are accessible by owner and group only. Others (normal users) aren’t allowed to access them.
I’ve tried a workaround – as root, I changed the owner to my own account – and that worked; I could access the devices. Of course, when I disconnected and reconnected the devices, /dev/ttyUSB* were owned by root again.
Is there a good way to make /dev/ttyUSB* automatically accessible for all users? (Btw., it works fine in Tumbleweed. There I have no problems with those devices.)
@afalb Hi, add your user to the dialout group, log out, log in and enjoy 
Please always show what you did to get the information you are now forwarding in story telling. E.g.
ls -l /dev/ttyUSB*
Then we can see e.g. which group.
Sorry for my delayed response.
Adding my user account to the dialout group didn’t help 
But adding the account to groups tty did the trick 
However, the output of the ls command still is as follows:
crw-rw----. 1 root dialout 188, 0 Mar 27 18:20 /dev/ttyUSB0
crw-rw----. 1 root dialout 188, 1 Mar 27 18:20 /dev/ttyUSB1
That doesn’t line up with the permissions on those device nodes.
More likely the software isn’t actually using /dev/ttyUSB*, but a different device such as /dev/tty, /dev/pts/0, or another control interface that happens to be owned by the tty group.
I agree that the permissions of /dev/ttyUSB* seem strange and that they look like I should never be allowed to access the devices as a normal user. Anyway, my setup is as follows:
There are two USB-Serial converters connected to my computer. Their serial interfaces are connected with a crossing serial cable.
Starting cat /dev/ttyUSB1 in one console window (as a standard user) and running ls -l -R >/dev/ttyUSB0 in another one has the desired effect: I can see the directory listing in the first console window. So it is definitely possible to access the devices.
@afalb Could also be SELinux… I’ve no issues with USB Serial when my user is added to the dialout group, but not tested on leap 16.0.
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