The *samba-dc* role now configures `winbindd` on domain controllers to
support identity mapping on the local machine. This will allow domain
users to log into the domain controller itself, e.g. via SSH.
The Fedora packaging of *samba4* still has some warts. Specifically, it
does not have a proper SELinux policy, so some work-arounds need to be
put into place in order for confined processes to communicate with
winbind.
The BIND9_DLZ plugin turned out to be pretty flaky. It craps out
whenever `named` is reloaded, which seems to happen occasionally for
reasons I cannot identify. Combined with the weird SELinux issues, and
the fact that upstream recommends against it anyway, I decided to just
use the built-in DNS server in Samba.