Note the primary and target standby must have connectivity for this command to complete successfully. You can upgrade the protection mode later, if necessary, as described in Setting the Protection Mode for Your Configuration. In maximum performance mode, the ability to automatically failover is restored Broker can be configured to initiate failover on any of the following conditions. Step 4: Enable Fast-Start Failover Now we are ready to enable FSFO: DGMGRL> enable fast_start failover; Enabled in Zero Data Loss Mode. While Oracle 11g's Data Guard definitely protects a database when the entire production site is lost via its failover capabilities, it's still necessary for an Oracle DBA to intervene to complete the failover process. When enabling fast-start failover, the broker verifies that the property indicates an existing standby. If there is only one standby database in the configuration, you can skip this step and continue with Task 3. If the specified log file is not accessible, or the LOGFILE IS option is not used, then the observer output is sent to standard output. Issue the following command while connected to any database in the broker configuration, except the database that is to be reinstated: The newly reinstated standby database will begin serving as a standby database to the new primary database. 12c Dataguard, In There are many examples, and Ritesh Chhajer offers this example of doing a Data Guard switchover using dgmgrl: 1. This exercises the configuration, but triggers failover differently than losing contact with the primary. Immediate: No additional data is applied on the standby database, resulting in a data-loss . The broker selects a target based on the order in which they are specified on the FaststartFailoverTarget property. FB Page:https://www.facebook.com/dbahariprasath/? Notice that the terminal session appears to hang after starting the observer. OBSERVER command, if this directory does not have the If fast-start failover is enabled and the Datafile Write Errors condition is specified, then a fast-start failover is initiated if write errors are encountered in any data files, including temp files, system data files, and undo files. Archiver is unable to archive a redo log because the device is full or unavailable. *PATCH V3 0/6] ASoC: codecs: Add Awinic AW883XX audio amplifier driver [not found] <000701d8e7521f78bc05e6a340awinic.com> @ 2022-11-11 11:26 ` wangweidong.a 2022-11 . The default value is ALL. Note: If you have just enabled archivelog mode, force an archive log creation ( alter system archive log current) to ensure that at least one archive log exists. To restore your original disaster-recovery solution after switchover to a logical standby database or after failover to any standby database, you may need to perform additional steps. Sign in to Azure See Choosing a Target Standby Database for helpful advice. The word ALL cannot be used as a group name because it is a reserved keyword. The example uses 10 seconds. The syntax for the configuration declaration is: The definition for each broker configuration is: The configuration-name can be different from the name defined in the metadata of the Data Guard Broker configuration. This article - the seventh in this ongoing . Depending on the failover and the types of standby databases involved, some of the databases may need to be reinstated or re-created. We want the observer to be able to automatically reinstate the former primary as a standby after our failover tests, so before each test, make sure that Flashback Database has at least 30 minutes of history. Bystander standby databases may be disabled by the broker during the failover, and they must be reinstated or re-created before they can serve as standby databases to the new primary database. Unlike ORLs, SRLs should be created with only one member per group. If the master observer detects an availability problem with the primary database, then it typically attempts to reconnect to the primary database within the time specified by the FastStartFailoverThreshold configuration property. A simple example for *nix is provided below that will work with both releases. 2. ZERO DATA LOSS: Fast-start failover is enabled with zero data loss. PRIM>SHUTDOWN IMMEDIATE; Metadata for the fuzzy snapshot is stored in the flashback log itself. The configuration status returns the SUCCESS status after the observer reestablishes its connection to the primary database, which then notifies the target standby database. See Manual Failover for complete information about manual failovers. Among many benefits of using this utility, I highlight that while using it, it will not need manual intervention to recover the databases or eventually a switchover in case the primary database becomes unavailable. (If there are other conditions, unique to an application, that would warrant a fast-start failover then the application can be set up to call the DBMS_DG.INITIATE_FS_FAILOVER function and start a fast-start failover immediately should any of those conditions occur. Without the credentials, Broker will complete the role transition, but will leave the databases in need of a manual restart. Alternatively, you can query the V$DATABASE view on the target standby database. The platform provides comprehensive services such as maintaining and monitoring databases to help the oracle databases in surviving during data corruption. DNS CNAME) that always resolves to the primary. Look for the desired data in the RAM. fast-start failover. database is managed by Oracle Clusterware, broker directs Oracle Clusterware to If the The service can be started on the physical standby only after the redo generated by starting the service has been applied. But it will also continue trying to reconnect to the primary database indefinitely. A switch-over allows the primary database to switch roles with its standby database. orapwd file=$ORACLE_HOME/dbs/orapw$ORACLE_SID. Immediately after issuing command in step 2, shut down and restart the standby instance STAN: The new ConfigurationWideServiceName configuration property can be used to simplify setting up this connect identifier. Use the oraenv script provided by Oracle. Oracle Data Guard with Fast-Start Failover (FSFO) can provide additional resiliency by setting up the broker on a separate machine. Whereas a switchover to a logical standby database will invalidate and disable all of the physical and snapshot standby databases in the configuration. multiple, inexpensive servers is the basis for the failover and other fault-tolerance features that RAC provides. Flashing back a database occurs in two stages: For FSFO environments, set db_flashback_retention_target = 60 or higher to provide sufficient Flashback Database history for automatic standby reinstatement. SQL> Select Database_role from v$Database; Hi, I am working in IT industry with having more than 10 year of experience, worked as an Oracle DBA with a Company and handling different databases like Oracle, SQL Server , DB2 etc If reinstatement of a database fails, its status changes to ORA-16795: the standby database needs to be re-created. A switchover is a role reversal between the primary database and one of its standby databases. After FSFO is enabled, Broker will continue to check that Flashback Database is enabled during health checks. November 20, 2009. Client-side broker The following sections describe how to reinstate or reenable a database. multi-tenant environments Know the database downgrade steps in case the upgraded database isn't compatible with the environment Discover the features and benefits to the organization when it moves from the old database . Maximum availability SYNC or FASTSYNC or ASYNC, Maximum performance SYNC or FASTSYNC or Being FSFO ready means that all conditions are met for a successful failover, including having a running observer and sufficient redo transmitted to the failover target to meet durability requirements. It is actually a low-footprint OCI client built into the DGMGRL CLI (Data Guard Broker Command Line Interface) and, like any other client, may be run on a different hardware platform than the database servers. Use the SQL ALTER DATABASE MOVE DATAFILE command to rename or relocate an online data file on a physical standby that is a fast-start failover target if the standby is mounted, but not open. There can be up to four Here's a one-liner observer startup for *nix. If the database is managed by Oracle Clusterware, broker does not open any of the To configure fast-start failover in observe-only mode: Fast-start failover will not be triggered if the primary or standby database is shut down normally. However, the event notifying a failover is only published for database services that have been configured to be active while the database is in the primary role on the new primary database. Add the SRLs. To switchover to a standby that is not the current failover target: John Smiley [jrsmiley@gmail.com] is a persistent storage architect for a major online retailer. FastStartFailoverLagLimit Your email address will not be published. The remaining Data Guard-related parameters will be set by Broker later in the walkthrough. When you run commands that need access to the observer The targets are referred to as candidate targets. Note: You can also use TNS aliases defined in the tnsnames.ora file when setting the local_listener parameter. automatic failover feature in configurations set up for zero data loss protection at any 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. Immediate Failovers in Configurations Using Cascaded Standbys. Table 6-3 FS_FAILOVER_OBSERVER_PRESENT Column of the V$DATABASE View, The master observer is currently connected to the local database, The master observer is not connected to the local database. The environment is a single instance database without any grid Infrastructure components. Verifies that the primary and the target standby databases are in the following states: The primary database is enabled and is in the TRANSPORT-ON state. The previous examples dealt with setting up only one service on a database. by the current operating system user who is running DGMGRL The subdirectories When the process is complete, the database will be enabled as a standby database to the new primary database, and Cloud Control displays the Oracle Data Guard Overview page. files include the observer configuration file (observer.ora), observer log Fast-start failover will not be attempted for the other types of database shutdown (NORMAL, IMMEDIATE, TRANSACTIONAL).