SSSD principle:
SSSD for SuSE (sles):
https://www.suse.com/support/kb/doc/?id=7022002
http://www.novell.com/support/kb/doc.php?id=7014572
RHEL:
Troubleshooting SSSD:
Resolution: id <userid> ; getent passwd <userid>
Authentication: ssh <userid>@localhost
In addition to redhat guide, there are tones of interesting links:
http://www.chriscowley.me.uk/blog/2013/12/16/integrating-rhel-with-active-directory/