CentOS 7.3 domain users сan not start a session xpra

[alexnur]

Hi!

CentOS 7.3 join to realm Windows Server 2008 R2 use samba/winbind. Realm 'ABC'.
Domain users are successfully authorized on the server CentOS 7.3 use domain credentials.

Domain users сan not start a session xpra (http://www.xpra.org) use ssh:

[user@srvusi06 ~]$ xpra start --start-child=firefox --bind-tcp=0.0.0.0:10002
2017-08-08 16:17:47,728 server failure: disconnected before the session could be established
2017-08-08 16:17:47,728 server requested disconnect: server error (failed to start a new session)
Warning: cannot use the system proxy for 'start' subcommand,
FAILURE
[user@srvusi06 ~]$ Entering daemon mode; any further errors will be reported to:
/run/user/16777219/xpra/S3383.log
Actual display used: :1
Actual log file name is now: /run/user/16777219/xpra/:1.log

Error:

File "/usr/lib64/python2.7/site-packages/xpra/server/server_core.py", line 565 , in add_listen_socket
sock.listen(5)
File "/usr/lib64/python2.7/socket.py", line 224, in meth
return getattr(self._sock,name)(*args)
socket.error: [Errno 22] "invalid argument".

Local users CentOS successfully start xpra session.

Tried to include the domain user in the local group 'xpra', does not help.

I tried changing the main group to the domain user "user":

[root@srvusi06 ~]# usermod user -g xpra
Usermod: user "user" does not exist in /etc/passwd

I manually added a line to /etc/passwd (982 - its gid xpra):

user16777219:982::/home/ABC/user:/bin/bash

Everything worked! The session started, I was able to connect to it from a remote computer.
However, now the command

[root@srvusi06 ~]# getent passwd

returns 2 users "user" with the same ID:

...
alex1002:1003::/home/alex:/bin/bash
user:16777219:982::/home/ABC/user:/bin/bash
administrator:*:16777216:16777216:administrator:/home/ABC/administrator:/bin/bash
guest:*:16777217:16777217:guest:/home/ABC/guest:/bin/bash
krbtgt:*:16777218:16777216:krbtgt:/home/ABC/krbtgt:/bin/bash
user:*:16777219:16777216:User aa. family:/home/ABC/user:/bin/bash
....

It's probably wrong ...
How to allow domain users to run xpra? Similarly connected to the domain of CentOS 6.9. There are no problems with running xpra domain users.