Nova can authenticate against a number of sources. By default, it
will use the local configuration database (the one specified by the
--sql_connection flag) for this.
However, the current version of Nova also supports LDAP for
authentication. LDAP authentication requires significantly more setup.
Setup help is available for OpenSSH, OpenLDAP, Sun’s LDAP, and OpenDJ. For
more information about setting up these options, consult the nova/auth/ directory in the Nova source.