If you want to capture any logging generated by the observer, use the LOGFILE IS option on the START OBSERVER command, and ensure that the file name is unique. Instead, the old primary database must be re-created as a standby from a backup of the new primary using the procedure described in How to Re-create and Reenable a Disabled Database. For any work, queries and help. list of the observers that can become the master observer when that 2) Switchover/Failover option is disabled on Enterprise Manager.What are the steps to enable it so that I can do Switchover/Failover operation using OEM. isolated. created when the START OBSERVER command is issued. See Oracle Data Guard Concepts and Administration for information about tuning the log apply rate for a physical standby database. We suggest you try the following to help find what youre looking for: This document will guide you through configuringOracle Data GuardFast-Start Failover (FSFO) using a physical standby database. When you configure data guard using OCI console, the default mode is set to maxprotection. If you don't already have a Flash Recovery Area (FRA), you will need to create one for Flashback Database. Broker keeps its configuration details in flat file. Initiate reinstatement by mounting the database. In addition, the primary database will shut down if it perceives a loss of connectivity for a period longer than FastStartFailoverThreshold seconds, if the FastStartFailoverPmyShutdown configuration property is set to TRUE. If you already have an FRA, you may need to increase its size in order to accommodate the Flashback Database files. issue commands and interact with the broker configuration. For this build, we will use a single physical standby database. This walkthrough assumes that all ORLs and SRLs on the primary and standby databases are the same size. 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. The subdirectories that DGMGRL creates under this directory will also have the If no name is specified for the observer then a default observer name, the host name of machine where the START OBSERVER command is issued, is used. In order to maintain separation of Broker and non-Broker activity, a second static service is recommended. By choosing the standby database with the least amount of unapplied redo, you can minimize the overall time it takes to complete the switchover operation. lag is less than or equal to the value specified by the This database property is used to specify how the observer should connect to and monitor the primary and standby database. This prevents a "split brain" condition if a failover occurs since none of the changes made to the isolated primary can be made permanent. by the current operating system user who is running DGMGRL The subdirectories Broker can be configured to initiate failover on any of the following conditions. Slightly less critical than making sure you've got a good primary is making sure the failed primary can be automatically reinstated. observer immediately begins monitoring the status and connections to The time interval specified by the FastStartFailoverThreshold property is ignored if the master observer detects that a user-configurable condition has occurred or if a fast-start failover has been requested by the DBMS_DG.INITIATE_FS_FAILOVER function. If the primary database does not have connectivity with the target standby database, fast-start failover remains enabled on the target standby database and the observer may still attempt a fast-start failover if conditions warrant a failover. If the target standby database is a snapshot standby database, all of its instances must be restarted to the mount mode before performing failover. You must determine which available standby databases should be targets for failover. Use the EMCLI verb dg_configure_observers. In the following example commands, a service named PAYROLL is configured to be active in the PRIMARY role on the primary database NORTH. ERROR: Unable to verify the graphical display setup. To enable fast-start failover in Cloud Control, use the Fast-Start Failover wizard. The master observer never waits for the threshold to expire to perform a fast-start failover in the following situations: If the master observer determines that any of the user-configurable conditions has been detected, then it attempts a fast-start failover. You must use the Oracle wallet to store the credentials for all broker configurations to be managed. Fast-start failover enables the Data Guard broker to rapidly and automatically failover to a previously chosen standby database without requiring manual intervention. For more details about managing redo transport services using database properties, see Managing Redo Transport Services. Starting Observers as Background Processes. These clients can be configured for Fast Connection Failover (FCF) to automatically connect to a new primary database after a failover. An existing connection which is already closed from the database side would throw an error. the location of the observer log file, and the location of the observer runtime data flashback logs on that database. Make sure the last redo data transmitted from the Primary database was applied on the standby database. We can always fail over to it or have it happen automatically if for some reason the primary Managed Instance has [] groups used by multiple configuration commands. This file contains connect identifiers to both the primary and the target standby databases. Determining a Database's Readiness to Change Roles. observer_hostname.log. In Oracle Database 11g, the password file on the standby must be a physical copy of the password file on the primary due to security enhancements introduced in Oracle Database 11g. Starting with 10.2.0.4 (including all versions of 11g and later), Oracle provides the FastStartFailoverPmyShutdown Broker property that allows you to specify what the primary should do if it is still in a stalled state when the FSFO threshold timeout has elapsed. You can optionally indicate the database health conditions that should cause fast-start failover to occur. 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). FastStartFailoverLagLimit property. Start the Data Guard listener on both "a" and "b" hosts. Choosing the standby database with the smallest transport lag can minimize the amount of data loss and in some cases, incur no data loss at all. Managed recovery process has been stopped between primary and standby database and standby becomes primary database. DGMGRL can be used to manage multiple observers in a group of broker configurations. Subdirectories within receives redo data from a far sync instance. 12c Dataguard, In Controlfile is permanently damaged because of a disk failure. add service command. The command SHOW FAST_START FAILOVER shows a list of registered observers and indicates which one is the master. The observer does not attempt to reinstate the former primary database. Multiplexing SRLs merely adds unnecessary IO and can increase commit latency. If failover is not possible for some reason, then the master observer will continue checking whether the standby database is ready to fail over. It wouldn't be much of a test if we didn't verify that our durability constraints were being met, so let's make a change on the primary and see if it survives the failover. FastStartFailoverLagLimit If you like a connect-time failover to survive across a data guard switchover, you need another way to do it. It will also alert you to databases that have had Flashback Database disabled at some point after FSFO was enabled. This can be avoided by first disabling fast-start failover with the FORCE option on the target standby. The example uses 10 seconds. SQL>connect /@STAN as sysdba Reinstatement will have to be accomplished by other means (manual or scripted Broker commands). A number of prerequisites must be met on the primary in order to use Fast-Start Failover. This allows the appropriate Data Guard services, such as redo transport or redo apply, to be started when the database is restarted later for any reason. Additionally, the new master observer is identified in the output shown for the SHOW FAST_START FAILOVER and SHOW OBSERVER commands. If you have not used the SET ObserverConfigFile command after starting the current DGMGRL client, then the result will always be: ObserverConfigFile=observer.ora. This section describes how to configure and verify each prerequisite. Note that the new primary database does not need to be restarted. There is no data loss during a switch-over. Create a trigger based on the, Oracle Database PL/SQL Language Reference, Choosing a Target Standby Database for Switchover, Choosing a Target Standby Database for Failover, Scenario 9: Performing a Switchover Operation, Scenario 10: Performing a Manual Failover Operation, Database Service Configuration Requirements, Troubleshooting Problems During a Switchover Operation, How the Broker Performs a Complete Failover Operation, How the Broker Performs an Immediate Failover Operation, Setting the Protection Mode for Your Configuration, Scenario 7: Enabling Fast-Start Failover When a Far Sync Instance Is In Use, Description of "Figure 6-1 Relationship of Primary and Standby Databases and the Observer", Enabling Fast-Start Failover Task 7: Configure Actions Before and After Fast-start Failover (Optional), Directing a Fast-Start Failover From an Application, Fast-start Failover Callout Configuration Files, Oracle Data Guard Command-Line Interface Reference, Description of "Figure 6-2 The Observer in the Fast-Start Failover Environment", Oracle Enterprise Manager Command Line Interface. In a DataGuard environment when the Primary instance fails you need to go through the Failover and Reinstate processes in order to restore the database service, as described in the documentation: Changes a standby database to the primary role in response to a primary database failure.