[Samba] What is Samba_dsdb???

[Greg Zartman]

In the configuration parameters created by samba-tool interactive, I get
passdb backend = samba_dsdb, but I have no idea what kind of backend this
is.  It also doesn't seem to be documented anywhere.

Further down the config, it mentions tdb as the backend for winbind.

It's a little unclear to me if Samba 4 uses LDAP auth out of the gate or
you have to do something to configure it.

Greg