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. https://www.facebook.com/dbahariprasath/? PRIM>connect /@PRIM as sysdba ERROR: Unable to verify the graphical display setup. You can use this information to identify ahead of time any redo transport configurations that would be incorrect after a role change, including any standbys that will not receive redo because the RedoRoutes property was not configured correctly. Initiate reinstatement by mounting the database. The FastStartFailoverTarget configuration property on the primary unless the new property value contains the current fast-start failover target. Add the SRLs. That process is shown here. Ensure this file cannot be read by unauthorized users. FSFO configurations in Maximum Performance mode may limit potential data loss by specifying the maximum allowable age of transactions that are lost during a failover. These conditions are described in the following table: Dictionary corruption of a critical database. The default value is 30 seconds. However, re-enabling Flashback Database will require a bounce since the database must be mounted and not open. Cancel MRP process. Because fast-start failover was not disabled on the target standby database, the observer may still attempt a fast-start failover to the target standby database should conditions warrant a failover. Table 6-2 FS_FAILOVER_STATUS Column of the V$DATABASE View. directory does not have the required permissions. Apply services on all other bystander standby databases automatically begin applying redo data received from the new primary database. Reinstatement restores high availability to the broker configuration so that, in the event of a failure of the new primary database, another fast-start failover can occur. A fast-start failover to the target standby database fails. The v$database view has has columns specifically for monitoring FSFO status. If the Broker configuration is changed to make a bystander the new failover target (probably a good idea if the failed database will be down for a while), the observer will not automatically reinstate the former primary because it is no longer part of the FSFO configuration. If the database is managed by Oracle Clusterware, broker does not open any of the The FastStartFailoverThreshold time interval starts when the observer first detects there might be a failure with the primary database. In such cases, the failed primary database is reinstated as a physical standby database. To avoid problems due to timing variations, values less than 60 minutes are not recommended and values of 30 or less virtually guarantee Flashback Database failure. A failed ping is a ping to Oracle Database PL/SQL Packages and Types Reference, Stop the observer from any computer system in the broker configuration, as described in, Start the observer on the new computer system, as described in Step 8 of, Enable fast-start failover using the DGMGRL, Shut down the primary database and the target standby database using either DGMGRL, Oracle Database Global Data Services Concepts and Administration Guide, Oracle Real Application Clusters Administration and Deployment Guide, Configure the connect descriptor for connect-time failover. 4. Then, on the Failover Confirmation page, click Yes to invoke the default Complete failover option. This can be done regardless of whether the failover was done to a physical, logical, or snapshot standby database. Setting this property to 'TRUE' (the default) causes the primary to self-terminate. 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. For this build, we will use a single physical standby database. Perform a switchover to a standby database that is not configured as the fast-start failover target, Perform a switchover to the target standby database in a configuration operating in maximum availability mode, unless the standby database is synchronized with the primary database, Perform a switchover to the target standby database in a configuration operating in maximum performance mode, unless the standby database is within the lag limit of the primary database. The new standby database is a viable target of a failover when it begins receiving redo data received from the new primary database. On Windows, the directory specified by the DG_ADMIN The Column Value in the following table is consistent across instances in an Oracle Real Applications Clusters (Oracle RAC) environment. A number of prerequisites must be met on the primary in order to use Fast-Start Failover. Problems with automatic reinstatement are frequently due to misconfiguration, so let's look at this in a bit more detail. The time interval starts when the observer first loses its connection to the primary database. This is cleared on both when the reinstatement has been completed. property. Regardless of the method you choose, the broker coordinates the role transition on all databases in the configuration. If a group name is not specified, then SHOW OBSERVERS alone is also a valid command. fsfo_hostname.dat. In the following example commands, a service named PAYROLL is configured to be active in the PRIMARY role on the primary database NORTH. 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. Before a The information in this guide is based on practical experience gained from deploying FSFO in a global corporate production environment. For more information, see START OBSERVER IN BACKGROUND. The master observer waits the number of seconds specified by the FastStartFailoverThreshold configuration property before attempting a fast-start failover when the primary database has crashed or has lost connectivity with the observer, as in the following situations: The primary database loses its connections with both the observer and target standby database. Displays the current fast-start failover mode. For example: You can find information about the master observer by querying the V$DATABASE view. connection, or the database on which you issued the disable fast-start failover Use the callout configuration file and script Starting Multiple Observers On a Single Host. After a failover, the original primary database can no longer participate in the Data Guard configuration. Both Cloud Control and the DGMGRL CLI will do this automatically as part of failover. Role Transitions: Switchover and Failover 1 -7 Oracle Data Guard Broker Framework 1 -9 C hoosing an Interface for Administering a Data Guard Configuration 1 -10 Oracle Data Guard: Architecture (Overview) 1 -11 Primary Database Processes 1 -12 . this script is run before the fast-start failover is initiated. Reference architectures for Oracle databases on Azure - Azure Virtual The broker allows an immediate failover to proceed even if there are errors present on the standby database that you selected to participate in the failover. After the broker receives the STOP OBSERVER request, the request is passed to the observer the next time the observer contacts the broker, and the observer then stops itself. START OBSERVING [cfg_group_name] starts a new observer for each broker configuration in the specified group. Note that the database will not open at this point. Synopsis. Whether or not you need the FORCE option depends mostly on if the primary and target standby database have network connectivity: If the primary and target standby database have network connectivity, and the database to which you are connected has network connectivity with the primary database, the FORCE option has no effect. In such a case, no attempt is made to transmit any unsent redo from the cascader to the terminal standby. The following is a sample observer configuration file: Since the broker configuration SALES consists of three databases, Boston, Chicago, and Dallas, with a CONNECT_ID of SALES_P, the SALES_P connect identifier must be defined such that it can reach any instance of any database within the configuration. OBSERVE-ONLY: Fast-start failover is enabled in observe-only mode. been enabled on the database prior to the failover and there must be sufficient Use the oraenv script provided by Oracle. These clients can be configured for Fast Connection Failover (FCF) to automatically connect to a new primary database after a failover. Oracle Database 11g observers are incompatible with 10g databases and vice-versa. It is instructive to watch the alert logs on both databases as well as the observer log after aborting the primary to gain insight into what happens during FSFO failover. The services required on the primary database are: Log Writer Process (LGWR) - Collects redo information and updates the online redo logs. Oracle Data Guard Broker is a utility that can help you manage your Oracle Data Guard. If fast-start failover is already enabled, the You cannot create the standby DB system in a different AD from the primary DB system. After the failover completes, the former primary database is automatically reinstated as a standby database when a connection to it is reestablished, if the FastStartFailoverAutoReinstate configuration property is set to TRUE. In disaster situations where a failover is necessary, you may be more limited as to which standby database is the best one to pick up the failed primary database's activities.