Su client is not working in daemon mode

[maf123sp]

I've try to migrate a running rserve installation from one system to another one.

Original version:
Ubuntu 22.04.3 LTS
R 4.1.2

Target:
Rocky Linux release 8.9
R 4.3.2

The Rserve.conf is identical. We are using TLS, Ip restricted access, passwords with distinct auth.function and also "su client" to use a restricted user environment for the R scripts.

On the original system we have a system service, which starts the Rserve in daemon mode. (the daemon keyword in Rserve.conf is set to FALSE, instead we are using --RS-set daemon=enable)

This works perfect!

On the target system we run into a problem. The "su client" is not working in daemon mode. If I start the command line manually the Rserve server starts and can process scripts. The login on client side works perfectly using the "auth.function". Also the "su client" in combination uid and gid works well. But as soon I start the same command line as service, it blocks any login command. It works as service, if I remove the uid and gui commands from Rserve.conf.

I guess, UI have a problem with user permissions, but I don't have any glue, what it could be. I've checked all permissions and use root as service user.

Is there any idea, what it could be? How can I find the root cause? Is theer any chance to get more, detailed information out of the Rserve server?

Thanks for any help,

Matthias