You must specify it every time you start a new DGMGRL client. specified by the ObserverPingInterval property. 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. To failover, connect to the standby database and use the DGMGRL FAILOVER TO db-unique-name command. Manual failover to the fast-start failover target can be performed without receiving an acknowledgement from the observer. That process is shown here. The configuration status returns the SUCCESS status after the observer reestablishes its connection to the primary database, which then notifies the target standby database. Displays when the primary and target standby databases are synchronized and the configuration is operating in maximum availability mode. the observer configuration file is observer.ora. milliseconds and that of ObserverRetryCount is 10. Starting with Oracle Database Release 21c, use the DG_ADMIN You the primary role, use the PreferredObserverHosts LinkedIn:https://www.linkedin.com/in/hari-prasath-aa65bb19/ However, fast-start failover cannot occur when the target standby database is in an unobserved state. (This is useful because the name defined in the metadata may contain whitespace and international characters, which the observer configuration file does not allow.). The existence of a .suc file, failover to the target standby database. See the START OBSERVER command for more information. If you expect the network to be disconnected for a long time and They may be reinstated if Flashback Database is enabled on those databases. fsfocallout.ora. The commands that can be executed for a group of configurations (as declared in an observer configuration file) are as follows. time, if all the sessions that are connected though the active services Therefore, the detection time can be reduced to nearly directory. Albino DeSantis - Senior System Engineer - US Coast Guard - LinkedIn Make sure that your OS environment on the standby is setup. Data Guard Physical Standby Setup in Oracle Database 11g Release 2 this script is run before the fast-start failover is initiated. 8.2 Private Cloud Appliance and . Oracle Data Guard can switch a standby database to the primary role in case a production database becomes unavailable due to . In this mode you will need to consider how much data loss is acceptable in terms of seconds and set the FastStartFailoverLagLimit configuration property accordingly. In addition, a logical standby database may contain only a subset of the data present in the primary database. The broker disables all of the physical and snapshot standby databases in the configuration. To see if your primary has already met a prerequisite, follow the instructions in the Verify section. Database services can be configured to be active in specific database roles on Oracle RAC databases and on single-instance databases managed by Oracle Restart. 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. In this case, no attempt is made to transmit any unsent redo from the far sync instance to the target physical standby prior to converting the physical standby into a primary database. Default value is 100 Use the 'show fast_start failover' command to see which user configurable FSFO failover conditions are in effect. See Manual Failover for complete information about manual failovers. the primary and target standby databases. The broker first converts the original primary database to run in the standby role. You can disable fast-start failover if necessary, by using the FORCE option. Additionally, the new master observer is identified in the output shown for the SHOW FAST_START FAILOVER and SHOW OBSERVER commands. distance. This is normal. In Maximum Availability mode, FSFO guarantees that no transaction that has received a commit acknowledgment will be lost during a failover. We could not find a match for your search. You can, however, perform a manual failover to a snapshot standby. [PATCH V3 0/6] ASoC: codecs: Add Awinic AW883XX audio amplifier driver same permissions. not already enabled, the observer waits until fast-start failover All other registered observers are considered to be backup observers. An application should use caution when calling the DBMS_DG.INITIATE_FS_FAILOVER function because the observer will initiate failover, if at all possible. The broker initiates a failover after the number of seconds specified by this See Directing a Fast-Start Failover From an Application). file (fsfo.dat). The broker never automatically reinstates the former primary database if a fast-start failover was initiated because a user configuration condition was detected or was requested by an application calling the DBMS_DG.INITIATE_FS_FAILOVER function. Alternatively, if you intend to switch back to the original primary relatively soon, then you may re-enable the disabled standby databases after the switch back. database is managed by Oracle Clusterware, broker directs Oracle Clusterware to Steps that require the primary to be in a mounted (not open) state are grouped together in the section below entitled Steps Requiring a Bounce of the Primary. It's generally a good idea to store the state file in a directory associated with the database to avoid locking issues when running multiple observers on the same host. STANDBY> ALTER DATABASE COMMIT TO SWITCHOVER TO PRIMARY; STOP OBSERVING, and SET observer name, host, whether it is the master observer, when it became the master Some of the statistics that can be monitored are as follows: LAST_FAILOVER_TIME that shows the timestamp of last fast-start failover, LAST_FAILOVER_REASON that shows the reason for the last fast-start failover. To achieve How to Test Data Guard Fast-Start Failover by Shutting Down Primary required permissions, the admin folder is created STOP OBSERVING [cfg_group_name] stops LOCAL observers running on this host (where this DGMGRL is running) for all broker configurations in a specified group. Oracle Database 11g FSFO adds support for Maximum Performance mode (async redo transfer), providing the flexibility to trade durability for performance. The default value is ALL. Examine the Broker configuration by logging into dgmgrl on the new primary. In maximum availability mode, the behavior depends on the value of the The DB_ROLE_CHANGE event will fire whenever a database is opened for the first time after a role transition. FastStartFailoverThreshold for reference information about the FastStartFailoverThreshold property. 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. 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. If the standby database is not enabled for management by the broker, then the failover cannot occur. In 10g, a single wallet can be used for multiple observers, but they must all use the same SYS password. Any apply delay must be removed before beginning a switchover. See Oracle Data Guard Concepts and Administration for information about tuning the log apply rate for a physical standby database. 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. The connect descriptor must contain the SERVICE_NAME parameter in either case. You must ensure that the primary database is shut down prior to performing a manual failover. Data Guard Failover Options - dba-oracle.com It uses the connect identifier specified in the observer configuration file to locate the credentials for a broker configuration from the Oracle wallet. If the status is SUCCESS, you're ready to start testing role transitions. ERROR: Unable to verify the graphical display setup. configuration scripts and checks for errors or misconfigurations. is only possible when the configured data loss guarantee can be The subdirectories that DGMGRL creates under this directory will also have the For switchovers, understanding all of the factors can simplify the choice of which standby database to consider as your new primary database. There is no need to multiplex SRLs in order to protect redo as with ORLs (the redo is already protected in the ORLs of the primary). Duplicate configuration names in configuration definitions are not allowed. It will also alert you to databases that have had Flashback Database disabled at some point after FSFO was enabled. The standby database must be re-created or reinstated before it can serve as a standby for the new primary database. Step 4: Enable Fast-Start Failover Now we are ready to enable FSFO: DGMGRL> enable fast_start failover; Enabled in Zero Data Loss Mode. The FastStartFailoverLagLimit configuration property is only used by the broker when enabling fast-start failover for configurations operating in maximum performance mode. In previous releases, OCI and ODP.NET clients receive FAN notifications via Oracle Advanced Queuing (AQ). SQL>ALTER SYSTEM SWITCH LOGFILE; When the conditions for fast-start failover are met, the Broker adds messages to the observer log and broker log indicating that fast-start failover would have been initiated. If there is only one registered observer, then it works in the same manner that a single observer worked prior to the advent of multiple observers in Oracle Database 12c Release 2 (12.2.0.1). In maximum protection mode, an automatic failover is always possible because the For example, if a physical standby database was in the APPLY-OFF state, it will remain in the APPLY-OFF state. Disabling fast-start failover without the FORCE option can succeed only if the database on which the command is issued has a network connection with the primary database and if the primary database and target standby database have a network connection. Follow the guidelines described in Choosing a Target Standby Database. file, observer runtime data file (fsfo.dat), fast-start failover callout No two observers on the same Data Guard Broker configuration can have the same name. 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. You can perform a manual failover even if fast-start failover is enabled. The target standby database when it does not have connectivity with the primary database, fast-start failover is disabled only on the target standby database. Synopsis. (Snapshot standbys are not included in the table because they are not supported as fast-start failover targets.). In order to apply redo data to the standby database as soon as it is received, use Real-time apply. Add the wallet location and override to sqlnet.ora. You can customize fast-start failover setup for a specific application by using the DBMS_DG PL/SQL package. The failover was to a logical standby database. Ensure this file cannot be read by unauthorized users. Services that must be active in any given database role (primary, physical standby, logical standby, or snapshot standby) must be configured with the Server Control utility (SRVCTL) explicitly on each database where the service must be active. 12c Dataguard, In In this case, disable fast-start failover using the FORCE option on the target standby database. Oracle Database 11g observers are incompatible with 10g databases and vice-versa. See Oracle Data Guard Concepts and Administration for more information on using the ALTER SYSTEM FLUSH REDO statement. In order to maintain separation of Broker and non-Broker activity, a second static service is recommended. For instance, you could log into the system running observer1 to stop observer2. The syntax for the optional definition of a broker configuration group is: The group definition section is optional. FSFO can provide substantial gains in high availability and disaster recovery preparedness for all environments, from inexpensive Cloud-based systems to global distributed data centers. Oracle 19c-Step by Step Manual Data Guard Failover Use the wrapper script to start the observer process when the observer host boots or to restart it if it dies. Note: Many of the Broker database properties correspond to database spfile parameters. Check the spelling of your keyword search. If there is another standby database that is available for failover, you can perform a manual failover to that standby database after you first disable fast-start failover using the FORCE option on that standby database. For zero data loss in maximum availability mode, the FastStartFailoverLagLimit property must be set to zero. The new primary database starts transmitting redo data to the new standby database. If a single-instance primary database (either Oracle RAC or non-Oracle RAC), or if all instances of an Oracle RAC primary database fail, the observer attempts a fast-start failover. Note that enabling FSFO does not make the configuration ready for automatic failover - that requires an observer, which we'll get to next. Performing failover : Step 1: Check Standby Database role. STAN is now transitioned to the primary database role.Now your PHYSICAL STANDBY Database has become PRIMARY. Overview of Switchover and Failover in a Broker Environment. You can upgrade the protection mode later, if necessary, as described in Setting the Protection Mode for Your Configuration. The remaining Data Guard-related parameters will be set by Broker later in the walkthrough. These conditions are described in the following table: Dictionary corruption of a critical database. RAM). If possible, confirm that fast-start failover has not Determining a Database's Readiness to Change Roles. When fast-start failover is enabled, the broker determines if a failover is necessary and initiates the failover to the current target standby database automatically, with no need for manual intervention. Testing FSFO failover requires simulating loss of the primary. Once an observer is started, no further user interaction is required. under the $DG_ADMIN directory. Although redo transfer is synchronous, Maximum Availability mode allows the primary to remain available if the standby database becomes unavailable for any reason (e.g. 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. These FAN events can be used in the following ways: Applications can use FAN without programmatic changes if they use one of these Oracle integrated database clients: Oracle Database JDBC, Oracle Database Oracle Call Interface (OCI), Oracle Data Provider for .NET ( ODP.NET), or Universal Connection Pool for Java. observer. Download Ebook Oracle 11g 12c Data Guard With Asm Lab Practice A If one of these errors has occurred, follow the guidelines in "Resolving ORA-752 or ORA-600 [3020] During Standby Recovery" in My Oracle Support Note 1265884.1 before proceeding. Flashing back a database is much faster and more seamless (one simple DDL statement) than traditional point-in-time or SCN-based recovery. After fast-start failover is enabled and up to four observers are started, one observer is nominated as the master observer that continuously monitors the environment to ensure the primary database is available. To specify which observer can be a master observer when a database is in Fast-Start Failover in Data Guard Environments on Oracle Cloud Observer uses the value of the DGConnectIdentifier property to connect to and monitor the primary and target standby databases. Fast-start failover can be used only in a broker configuration and can be configured only through DGMGRL or Cloud Control. The My Oracle Support note 1625597.1 at http://support.oracle.com for information about compatibility requirements between the observer and DGMGRL, Starting Multiple Observers on a Data Guard Broker Configuration. It behaves similarly to START OBSERVING and STOP OBSERVING to operate on all the configurations defined in the observer configuration file. lower detection times for primary database failures. The simplest way to do this is to abort the primary. The behavior of the broker if the master observer fails depends on whether the broker configuration has one observer or multiple observers. A failed ping is a ping to 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. To start an observer as a background process, use the DGMGRL Switchover and Failover with DataGuard Broker on Oracle 19c - Data Alchemy The following paragraphs describe the supported availability modes. A fast-start failover occurred because a user-configurable condition was detected or was requested by an application by calling the DBMS_DG.INITIATE_FS_FAILOVER function. Immediate: No additional data is applied on the standby database, resulting in a data-loss . See Setting the Protection Mode for Your Configuration. It can be useful to perform such queries because fast-start failovers are fully automated and can occur at any time. Data Guard Failover to physical standby Tips - dba-oracle.com For example, if all your physical standbys are also unavailable, then failing over to a logical standby is your only choice. As shown in the table, fast-start failover can be enabled in maximum availability Do this prior to every failover test. There is little risk in enabling Flashback Database to determine its storage requirements - it can be disabled while the primary is open if necessary. When the primary database and the target standby database regain network connectivity, the broker will disable fast-start failover for the entire broker configuration. If the configuration contains physical, snapshot, and logical standby databases, consider choosing a physical standby database as the target standby database. You must set both ), 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. The example uses 10 seconds. Configure one or more active standby databases Minimize downtime for upgrades The observer immediately initiates a fast-start failover, as long as the failover target database is in a valid fast-start failover state ("observed" and either "synchronized" or "within lag") to accept a failover. Chapter 9 of the Data Guard Broker documentation (10g and 11g) contains a description of each property. The act of switching roles should be a well-planned activity. To start an observer, you must be able to log in to DGMGRL with an account that has 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. The connect descriptor can be configured in one of two ways: Oracle Database PL/SQL Language Reference for more information about the DB_ROLE_CHANGE system event. Failovers become routine. One is the master Broker keeps its configuration details in flat file. There are prerequisites that must be met before the broker allows you to enable fast-start failover. It uses these databases as a copy of the . In this case, the FS_FAILOVER_STATUS and FS_FAILOVER_OBSERVER_PRESENT columns will appear as shown in the following table and fast-start failover will not occur: Oracle Database Reference for more information about the V$DATABASE view. There is no data loss during a switch-over. Once the observer is started, you cannot change the file's name and location. ORACLE-BASE - Data Guard add service command. observer is still in contact with the standby. Oracle Data Guard work on two database roles Primary and Standby. For each temporary table, verifying that temporary files associated with that table on the primary database also exist on the standby database. 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. broker opens all the PDBs on the new primary database and on the target standby 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. Broker Configuration Has Only One Registered Observer. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); This site uses Akismet to reduce spam. The OberverPingRetry property specifies the number of Switchover and Manual Failover for more information about switchovers and manual failovers, respectively. Initiate reinstatement by mounting the database. *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 . To change the FastStartFailoverTarget property to point to a different standby database, disable fast-start failover, set the FastStartFailoverTarget property, and reenable fast-start failover. To start an immediate failover, use the DGMGRL FAILOVER TO database-name IMMEDIATE command. After In the following example commands, a service named PAYROLL is configured to be active in the PRIMARY role on the primary database NORTH. Learn how your comment data is processed. Note that the database will not open at this point. Automatic failover for Autonomous Data Guard enabled Autonomous Oracle Data Guard is a solution provider to businesses by offering data protection and its disaster recovery along with its high availability. Using Cloud Control, you can view the value of the ApplyLag column for each standby database in the Standby Databases section of the Oracle Data Guard Overview page. Some properties have changed between those releases. PDF Steps To Configure Oracle 11g Data Guard Physical Standby This can be done regardless of whether the failover was done to a physical, logical, or snapshot standby database. However, there may be exceptions to the recommendation to choose a physical standby database as the target standby database. The command SHOW OBSERVER provides detailed information about registered observers. 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. A failover is a role transition in which one of the standby databases is transitioned to the primary role after the primary database (all instances in the case of an Oracle RAC database) fails or has become unreachable. Other members of the configuration will receive redo from the designated redo source based on the new primary. 1)What are the steps to do Switchover/Failover operation manually in 2-node RAC and 2-node DATAGUARD environment. The configuration and database status report that the observer is not running and return one of the following status messages: While the configuration is in the unobserved state, fast-start failover cannot happen. The reinstated database acts as the fast-start failover target for the new primary database, making a subsequent fast-start failover possible. 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.