Realm in Tomcat server.xml

      <Realm
        className="org.apache.catalina.realm.JNDIRealm"
        connectionURL="ldap://mydomain:389"
        debug="99"
        roleBase="ou=groups,dc=mydomain,dc=com"
        roleName="cn"
        roleNested="true"
        roleSearch="(member={0})"
        roleSubtree="true"
        userPattern="uid={0},ou=people,dc=mydomain,dc=com"
      />