backend database. Multiple suffix lines can be given and at least one is
required for each database definition.
.TP
+.B subordinate
+Specify that the current backend database is a subordinate of another
+backend database. A subordinate database may have only one suffix. This
+option may bse used to glue multiple databases into a single namingContext.
+If the suffix of the current database is within the namingContext of a
+superior database, searches against the superior database will be
+propagated to the subordinate as well. All of the databases
+associated with a single namingContext should have identical rootdns.
+Behavior of other LDAP operations is unaffected by this setting. In
+particular, it is not possible to use moddn to move an entry from
+one subordinate to another subordinate within the namingContext.
+.TP
.B updatedn <dn>
This option is only applicable in a slave
.B slapd.