For <em>Administrator Login</em> mode, <code>JNDIRealm</code> will be
    configured to establish one or more connections (using a connection pool)
    to an appropriate directory server, using JNDI APIs, under a "system
    administrator" username and password.  This is similar to the approach
    normally used to configure <code>JDBCRealm</code> to access authentication
    and access control information in a database.  It is assumed that the
    system administrator username and password that are configu