Ucs user can not Login at ubuntu client

Hi,

i setup a ucs and join a ubuntu client to the domain. This was succesfull. Then i
add new users on the server. But when i try to log in with this user on my ubuntu client this is not possible. Can someone tell me how to track this problem.

My setup is

UCS: 5.0-0 errata131
Installed: dhcp-server=12.0 m23=21.1-50 samba4=4.13
Upgradable:

This is my auth.log file

Oct 21 20:12:11 t440s gdm-password]: pam_unix(gdm-password:auth): check pass; user unknown
Oct 21 20:12:11 t440s gdm-password]: pam_unix(gdm-password:auth): authentication failure; logname= uid=0 euid=0 tty=/dev/tty1 ruser= rhost=
Oct 21 20:12:11 t440s gdm-password]: pam_sss(gdm-password:auth): authentication failure; logname= uid=0 euid=0 tty=/dev/tty1 ruser= rhost= user=testuser
Oct 21 20:12:11 t440s gdm-password]: pam_sss(gdm-password:auth): received for user testuser: 10 (Benutzer bei zu Grunde liegendem Legitimierungsmodul nicht bekannt)