There is a very informative Red Hat article about configuring sssd manually. The following instructions are a functional adaptation. For a more detailed understanding of what these config files and options mean, please start by reading the manpages for sssd, sssd-ad, sssd-krb5, sssd-ldap, sssd.conf, krb5.conf and smb.conf and the above article.
Sep 27, 2011 · SSSD does not currently run automatically on any system, nor is it presently required for your system to operate. We are an optional component, usable when you want network identity and authentication. Otherwise (and by default) we do not run on the system. At this time, SSSD doesn't interact with local users at all.