 This typically indicates a network problem where the standby site is unable to respond to the primary. In the event of this situation, examine the Data Guard broker log file on the primary site to determine which standby sites could not be reached. Then for each standby site not reached, connect to that site and shut down the broker by setting the DG_BROKER_START initialization parameter to false. After the broker has been shut down on the standby site, locate the Data Guard broker configuration files from the standby site's DG_BROKER_CONFIG_FILE[1 | 2] parameter values and delete them.