Unable to authenticate using SSSD against LDAP server after upgrade from RHEL6.1

Issue

We patched the server from 6.1 to 6.4. The LDAP config is still broken, and we need some assistance in getting it back on track!

• A normal ldapsearch does return the user list as configured in LDAP:

ldapsearch -x -H ldaps://<ldaphost>:636 -b "dc=<domain>,dc=<tld>"
...

• Same sssd.conf used as in 6.1.
• What we see now is errors in the /var/log/secure file when logging in via SSH or doing su -

Mar 21 12:35:18 <hostname> sshd[<pid>]: pam_sss(sshd:auth): received for user <someuser>: 9 (Authentication service cannot retrieve authentication info)