The connect descriptor must contain the SERVICE_NAME parameter in either case. Note that the database will not open at this point. If the observer finds that the database is no longer the primary, it will attempt to reinstate it as the failover target standby. If the value is zero, the standby must The following is an example of setting the LogXptMode property: Alternatively, use the RedoRoutes property to set the redo transport mode for the target standby and database that is currently in the primary role. To issue commands and interact with the Oracle Data Guard helps you change the role of databases between primary and standby using either a switchover or failover operation. (as it might in maximum availability and maximum performance modes). Immediate: No additional data is applied on the standby database, resulting in a data-loss . To verify this change, again query the Database_role column of V$DATABASE. If fast-start failover is enabled you can still perform a switchover or a manual failover as long as certain conditions are met. Valid values are >= 100. groups used by multiple configuration commands. The rest of this section provides examples of using DGMGRL SHOW commands to display fast-start failover information and includes sections describing the following views: The DGMGRL SHOW FAST-START FAILOVER command displays all the fast-start failover related information. Managed recovery process has been stopped between primary and standby database and standby becomes primary database. environment that is guaranteed to either lose no data (when the Setting it to 'FALSE' leaves the database open and stalled until it is terminated or signaled to proceed in the event a failover did not take place (e.g. If clients are already configured to automatically time out and reconnect if they don't get a response from the database, a simple but effective approach is to use a network alias (e.g. DG_ADMIN environment variable is not set, the files are stored in Look for the desired data in the RAM. Stop the observer using the DGMGRL STOP OBSERVER command. SQL> select name,open_mode,database_role from v$database; NAME OPEN_MODE DATABASE_ROLE --------- -------------------- ---------------- MYTEST MOUNTED PHYSICAL STANDBY Step 2: Apply the following command to finish database recovery. The minimum If block change tracking is enabled on the primary, and the target file also declares broker configurations and defines configuration this script is run before the fast-start failover is initiated. These are the guidelines for choosing a target standby database. gets enabled and then begins monitoring. You can upgrade the protection mode later, if necessary, as described in Setting the Protection Mode for Your Configuration. You can also reinstate bystander standby databases that were disabled during a failover operation. SHOW OBSERVER command to confirm that the switch took place. Default value is 100 The value specified for either of these properties should allow the master observer to connect to any instance of an Oracle RAC database. Now your old standby database is become primary database, it is highly recommended to consider immediate full backup of primary database. After the former primary database has been repaired, the observer reestablishes its connection to that database and reinstates it as a new standby database. You must specify it every time you start a new DGMGRL client. For the RMAN duplicate active database method, the init.ora file (initdb1.ora in the example) requires only one parameter: db_name (it doesn't even have to be the real name of the database - any name will do). ), The RedoRoutes property on a far sync instance if it is being used to receive redo from the primary database and ship redo to the target standby database, The standby database that is the target of fast-start failover, A far sync instance if it is being used to receive redo from the primary database and ship redo to the target standby database, Unless the conditions listed in Performing Manual Role Changes When Fast-Start Failover Is Enabled have been met, To a standby database that is not configured as the fast-start failover target. fast-start failover to the target standby database if conditions warrant a failover. The command SHOW OBSERVER provides detailed information about registered observers. We'll start with switchovers. Relationship Between Primary, Target Standby, and Observer During Fast-start Failover. the service configuration. Learn how to use Oracle Data Guard broker to manage databases during switchover and failover. You must re-create the database manually from a copy of the current primary database and then reenable the database in the broker configuration. Displays only on a logical standby database that has not yet completed loading a copy of the primary database's data dictionary. Do not attempt to reinstate the old primary database if an ORA-752 or ORA-600 [3020] error has occurred at the failover target. Enabling fast-start failover in a configuration operating in maximum performance mode provides better overall performance on the primary database because redo data is sent asynchronously to the target standby database. Upon detecting the break in communication, the observer attempts to reestablish a connection with the primary database for the amount of time defined by the FastStartFailoverThreshold property before initiating a fast-start failover. If you cannot tolerate any loss of data, then ensure that the configuration protection mode is set to maximum availability or maximum protection. When querying the V$DATABASE view, pay special attention to the following: The FS_FAILOVER_STATUS column, which can contain the values described in Table 6-2. This is to ensure that the service definition gets propagated to the physical standby database via the redo stream and thus allows for the service to be started on the physical standby database. become the master observer. Broker will set the primary to use asynchronous log transport by default. This allows for redundancy in your Data Guard observer setup as well. If the client uses remote ONS subscription, the client must specify the hostname and port of the ONS daemon(s) of the primary database and each standby database. You can, however, perform a manual failover to a snapshot standby. Start the Data Guard listener on both "a" and "b" hosts. command does not have a network connection to the primary database. You might, for instance, use this to allow the observer to monitor the databases using the same connect identifiers as the client applications. SQL>select sequence#, applied from v$archived_log; ORACLE instance shut down. If client-side ONS configuration is used, the client-side ONS configuration file must specify the hostname and port of the ONS daemon(s) of the primary database and each standby database. If the failover target database is an Oracle RAC physical or snapshot standby database, the broker directs Oracle Clusterware to restart all instances that may have been shut down prior to the failover. During an immediate failover, the broker performs the failover steps described in How the Broker Performs an Immediate Failover Operation. time specified by maximum configured Permissions Required by the DG_ADMIN Directory. Oracle Data Guard with Fast-Start Failover (FSFO) can provide additional resiliency by setting up the broker on a separate machine. FastStartFailoverThreshold for reference information about the FastStartFailoverThreshold property. DG BrokerDG BrokerData Guard BrokerOracleDGRMAN Duplicate . FastStartFailoverLagLimit configuration property is set to zero) or the ObserverPingRetry and ObserverPingInterval properties to achieve Note: this state also occurs on the primary during startup when fast-start failover is possible and neither the target standby database nor the observer are present to confirm it is okay to continue opening the database. In addition to setting the configuration protection mode to maximum performance, you will also need to ensure that the LogXptMode database property for both the primary and target standby database is set to ASYNC. If you are performing an immediate failover, then the database role is changed to primary without applying any accumulated redo data. To enable fast-start failover with DGMGRL, issue the ENABLE FAST_START FAILOVER command while connected to any database in the broker configuration, including on the observer computer. This property is measured in These scripts must be in the same directory as the Displays when the primary and target standby databases are synchronized and the configuration is operating in maximum availability mode. If the credentials cannot be obtained, then the attempted command fails (but only for the broker configuration whose credentials have not been obtained). You must ensure that the primary database is shut down prior to performing a manual failover. Cloud Control will start the observer. contains important information about the observer. Specifying the Observer Configuration File. This section lists the steps the master observer takes to determine if a fast-start failover is needed and then to perform one, if necessary. The following is an example of querying the V$FS_FAILOVER_STATS view: Disabling fast-start failover prevents the observer from initiating a failover to the target standby database. See Oracle Enterprise Manager Command Line Interface. The following list indicates the extent to which fast-start failover is disabled in the broker configuration when the DISABLE FAST_START FAILOVER FORCE command is issued on the primary database, target standby database, and a standby database that is not the fast-start failover target. With FSFO enabled, Broker expects to find an observer, which we haven't started yet, so if you verify the at this point with 'show configuration', Broker will report a warning (if it doesn't, give it a minute to discover that the observer isn't there). For Fast Connection Failover (FCF) to occur, a client must be able to locate the new primary database after a failover. Attempt to open the primary database, or the following error may be returned: This error may return if the fast-start failover validity check fails or does not complete in under two minutes. Note the primary and target standby must have connectivity for this command to complete successfully. standby database, host, or network failure, etc.). Media Recovery - Once the restore is complete, recovery proceeds as a typical media recovery, applying redo from archived and online redologs and rolling back uncommitted changes with undo. observer. See "Database Service Configuration Requirements" for additional information about how the broker interacts with Oracle Restart. irrespective of its content, indicates that the script executed successfully. After Fast-Start Failover: The fast-start failover has completed and the target standby database is running in the primary database role. See the START OBSERVER occur. In such a case, no attempt is made to transmit any unsent redo from the cascader to the terminal standby. the location of the observer log file, and the location of the observer runtime data They must be re-created before they can serve as standby to the new primary database. They can all be done at the same time in a single bounce. It comes with a GUI and command line interface. This is the recommended method for disabling fast-start failover. 5. This method will disable fast-start failover on all databases in the broker configuration. The old Primary must have been running in flashback mode before the failover. Check the Undo tablespace Usage in Oracle, Exclude/Include option in EXPDP and IMPDP Datapump, Missing Dependencies Python Core / win32api, Stop the EXPDP/IMPDP Datapump Job in Oracle, Find the temp usage by sessions in Oracle, Create & grant permission to directory in Oracle, Check the Patch Applied to the Oracle Database. FAN events are published using Oracle Notification Services (ONS) for all Oracle integrated database clients in Oracle Database 12c and later. If the agent is not However, if you want the observer to reconnect to the primary database periodically as a means of testing the health of the network connection to the primary, then use the ObserverReconnect configuration property. The NetTimeout property specifies the number of seconds LGWR will block waiting for acknowledgment from the standby in synchronous mode before considering the connection lost (corresponds to the NET_TIMEOUT option of log_archive_dest_n). RMAN will copy the spfile from the primary, so this init.ora file is only needed during the first phase of the duplication. Reinstate the original primary database to act as a standby database in the new configuration. Make some new changes and verify that they are preserved after failover. See Troubleshooting Problems During a Switchover Operation for more information. If you intend to switch back to the original primary database relatively soon, you may allow the physical and snapshot standbys to remain disabled. On primary database NORTH, execute the following: On standby database SOUTH, execute the following: Services that are to be active while the database is in the physical standby role must also be created and started on the current primary database regardless of whether the service will be started on that database or not. Manual failover to the fast-start failover target can be performed without receiving an acknowledgement from the observer. To stop it, you can do either of the following: Choose the Stop Observer option on the first page of the fast-start failover wizard and click Continue at the bottom of the page. In maximum performance mode, the ability to automatically failover is restored Data Guard Broker - Controls the creation and monitoring of Data Guard. The observer automatically starts the reinstatement process. This means that in order for a flashback database operation to succeed, observer and the standby both lose contact with the primary. The simple tests described in this guide are fine for making sure the basics are working, but you'll probably want to develop a more comprehensive set of tests suited to your environment and requirements. Verifies that the target standby database is enabled. Staff support, hardware and software, security (both software and site), network connections, and bandwidth should be equivalent at both sites. the names of the scripts created in the previous step. The column value for V$DATABASE.FS_FAILOVER_STATUS will be SYNCHRONIZED in a configuration operating in maximum availability mode, and it will be TARGET UNDER LAG LIMIT in a configuration operating in maximum performance mode when ready to fast-start failover. The environment is a single instance database without any grid Infrastructure components.