For example: The following example shows the fast-start failover information for the DRSolution configuration: The following SHOW OBSERVER command displays information about multiple observers in the DRSolution broker configuration. file, observer runtime data file (fsfo.dat), fast-start failover callout the primary database that failed or took longer than the time SQL>SHUTDOWN IMMEDIATE; environment variable must have exclusive permissions wherein it can be accessed only If this operation is successful, a zero data loss failover may be possible even if the primary database is not in a zero data loss protection mode. Note that this does not guarantee no data will be lost. However, no additional data is applied on the standby database once you invoke the failover. The broker allows the switchover to proceed as long as there are no errors for the primary database and the standby database that you selected to participate in the switchover operation. The FS_FAILOVER_OBSERVER_PRESENT column displays YES for the target standby database. This section describes how to configure an Oracle Net connect descriptor that meets this requirement. Use Recovery Manager (RMAN) to back up the PeopleSoft database on a regular backup schedule. FastStartFailoverLagLimit property. See Manual Failover for complete information about manual failovers. 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. 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. Indexing is a mechanism by which the underlying data is mapped for faster retrieval. You must then re-create it from a copy of the new primary database and reenable it as described in How to Re-create and Reenable a Disabled Database. Change the failover target to the standby being switched over to, Change the failover target to the desired standby. All database connections associated with the observer, including the initial connection, must use dedicated server connections. Unless action is taken to change the failover target to one of the bystanders, the new primary will be without a failover target until the former primary is reinstated as a standby. 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. FSFO builds upon a number of other Oracle technologies and features such as Data Guard, Flashback Database, and Data Guard Broker. The observer automatically starts the reinstatement process. The broker automatically reenables the database as part of reinstating it. Sign in to Azure If the target is a snapshot standby database, the broker first converts the database back to a physical standby and then starts Redo Apply to apply all the accumulated redo before completing the failover and opening the database as a primary database. In order for Flashback Database to succeed, there must be sufficient history available in the Flashback Database logs and all of the redo generated between the restore point and the standby_became_primary_scn must be available. If the former primary database cannot be reinstated automatically, you can manually reinstate it using either the DGMGRL REINSTATE command or Cloud Control. SHOW OBSERVER command to confirm that the switch took place. OBSERVER command, if this directory does not have the the current working directory. The observer host is 'observer.demo.org'. The configuration and database status report the same error messages as are returned when there is only one registered observer. See Disabling Fast-Start Failover. Any apply delay must be removed before beginning a switchover. If failover is not possible for some reason, then the master observer will continue checking whether the standby database is ready to fail over. 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. If fast-start failover is When both databases have been restarted, you may restart the observer. For Oracle RAC databases, see Oracle Real Application Clusters Administration and Deployment Guide for more information about configuring database services with the SRVCTL utility. 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. It will return PHYSICAL STANDBY, A failover to a logical standby database requires that all physical and snapshot standby databases be re-created from a copy of the new primary database after the failover completes. After a role change, the naming service can be updated with the new primary's address. An spfile is required to persist these changes. must ping the primary database. It must appear as the first part of an observer configuration file. But before enabling Flashback Database, you must enable Flash Recovery Area (FRA). Note that the new primary database does not need to be restarted. Any unsent redo data residing on the far sync instance is transmitted to the target physical standby prior to converting the physical standby into a primary database. The observer maintains state information in a file. Starts redo transport services to begin transmitting redo data to all bystander standby databases that were not disabled. Else, broker restarts the new When enabling fast-start failover, the broker verifies that the property indicates an existing standby. command for more information about starting the Flashback Database stores its logs in the Flash Recovery Area (FRA), so the FRA must be large enough to store at least 60 minutes of Flashback Database history. The following example shows you how to set up more than one service on a database and how using the broker ensures that the correct service starts on the correct database. Commands For Managing Observers on Multiple Configurations. 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. the preferred method for starting an observer. The only exception to this is failovers to snapshot standby databases. If an application has called this function and it has received a status of SUCCESS, then the master observer attempts a fast-start failover. Manual failover to the fast-start failover target can be performed without receiving an acknowledgement from the observer. Specifying the Observer Configuration File. operation can be automated using callout scripts. Use the EMCLI verb dg_configure_observers. If multiple observers have been started for the configuration, then be sure to specify the name of the observer whose environment is to be patched (STOP OBSERVER observer-name). Stopping the observer does not disable fast-start failover. Note: Data Guard requires dedicated server connections for proper operation. If there is only one standby database in the configuration, you can skip this step and continue with Task 3. Group definition this section is optional. Conditions shown in blue are enabled by default. Oracle recommends configuring Flashback Database on every database so that if failover occurs to a physical standby database, you can more easily reinstate any disabled standby databases. In addition, a logical standby database may contain only a subset of the data present in the primary database. command START OBSERVER IN BACKGROUND. Verify the standby database instance is mounted. The example uses 10 seconds. If only a file name is In maximum availability mode, set the LogXptMode database property for both the primary and target standby databases to SYNC or FASTSYNC. This can be compared to performing an RMAN restore of the datafiles from a backup taken prior to the specified SCN, but is much faster. Issue the DISABLE FAST_START FAILOVER command or the DISABLE FAST_START FAILOVER FORCE command. RMAN will copy the spfile from the primary, so this init.ora file is only needed during the first phase of the duplication. Expected output is shown in blue text. Broker changes database parameters during startup and role transitions via ALTER SYSTEM commands. Performing failover : Step 1: Check Standby Database role. 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. In order to fully automate switchover, Broker needs SYSDBA credentials in order to restart one or both databases. In the following example, a service named sales is configured to be active in the PHYSICAL_STANDBY role on the primary database NORTH. All physical and snapshot standby databases will be disabled and must be re-created from a copy of the new primary database after a switchover to a logical standby database. Failover:- In case of worst situation with data guard primary database, or not available for production than we can activated standby database as a primary production database. But it will also continue trying to reconnect to the primary database indefinitely. Because the broker performs the failover after converting the snapshot standby database to a physical standby database, it is likely that all standby databases in the configuration will still be available as standby databases to the new primary database after the failover operation completes. Since the observer is a specialized instance of a dgmgrl session, the observer host should be installed with either the Oracle Client Administrator software or the full Oracle Database software stack. lag is less than or equal to the value specified by the Cancel MRP process. This action may result in two databases in the configuration simultaneously assuming the primary database role should fast-start failover occur. 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. Displays if the standby database's redo applied point does not lag the primary database's redo generation point by more than the number of seconds specified by the FastStartFailoverLagLimit configuration property and the configuration is operating in maximum performance mode. Each group that you define must have at least one broker configuration. Tags: Data Guard, Oracle. This database property is used to specify how the observer should connect to and monitor the primary and standby database. Oracle Data Guard Broker is a utility that can help you manage your Oracle Data Guard. If the agent is not If there is only one observer, then it is considered to be the master observer. 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. 3. It's a good idea to have at least two hosts configured to run observers so that one can take over if the other fails. When a primary loses contact with both the failover target and the observer simultaneously, it enters a "stalled" state (v$database.fs_failover_status = 'STALLED') and any sessions still connected to the primary will block on commit. The name of the callout configuration file is fsfocallout.ora. occurred to the target standby database prior to disabling fast-start Oracle Data Guard helps you change the role of databases between primary and standby using either a switchover or failover operation. DGMGRL. To start the observer with DGMGRL, issue the following This allows Data Guard to remain functional during maintenance periods when the application listeners are down. In the rare event that a switchover operation fails and you are left with no primary database, retry the switchover command. Use the oraenv script provided by Oracle. The values that indicate FSFO is ready for failover are listed below. If the primary is unable to contact the standby after a user specified period of time (NET_TIMEOUT option of log_archive_dest_ n), it drops out of synchronous transfer mode and begins operating as though it were in Maximum Performance mode. Before enabling fast-start failover, use one of the following techniques What is true about data guard set up with fast-start failover (FSFO) in Oracle Cloud Infrastructure (OCI)? If the DG_ADMIN environment variable is not defined, or the milliseconds. In the restore stage, Flashback Database restores the database to a point prior to the standby_became_primary_scn using the before-image blocks in the Flashback Database logs. To allow the database to register with the Data Guard listener, the listener endpoint must be added to the database's local_listener parameter. If you will be using RMAN to create the standby database, it also needs a static service to restart the database being created. Then, click Continue to proceed to the next page. For this reason, you should first issue this command on the target standby database. In maximum protection mode, set the LogXptMode database property to SYNC (note that in maximum protection mode, a far sync instance cannot be used to ship redo to a standby). If reinstatement of a database fails, its status changes to ORA-16795: the standby database needs to be re-created. Refer to the appropriate Oracle RAC or Oracle Restart documentation for further information. In this case, the observer cannot perform a fast-start failover even if conditions warrant a failover. Errors occurring for any other configuration members will not impede the switchover. DGMGRL to manage multiple observers on multiple configurations. If the former physical standby database was running with real-time query enabled, the new physical standby database will run with real-time query enabled. This allows for redundancy in your Data Guard observer setup as well. this script is run before the fast-start failover is initiated. required permissions, the admin folder is created FB Group:https://www.facebook.com/groups/894402327369506/ In order to accommodate all load conditions, Oracle recommends having at least one more SRL group than the number of ORL groups of the same size. Tailing the alert logs on the primary and standby is a good way to watch Broker in action and get familiar with how it performs various tasks. SET ObserverConfigFile used to specify a customized observer configuration file. Sets up redo transport from the new primary to the other members of the configuration, Starts Redo Apply services on the new standby, Ensures the other standbys in the broker configuration are viable to the new primary, Integrates with Oracle Clusterware and Oracle Global Data Services (GDS) to ensure that the proper services are started after a role change. The database cannot provide fast-start failover status information. The existence of a .suc file, A running observer will follow the primary automatically after a role transition, but a newly (re)started observer won't start if the initial connection is to a down database or one with an out of date or corrupted Broker config file. WAIT option, broker waits for the amount of Create a unique connect alias for each 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. Databases that can be reinstated will have the following status value: For the REINSTATE command to succeed, Flashback Database must have The time interval starts when the observer first loses its connection to the primary database. Disabling fast-start failover with the FORCE option when connected to the target standby database guarantees that fast-start failover will not occur. Time for action - using interfaces to monitor Data Guard; Other replication solutions and Data Guard; Metadata for the fuzzy snapshot is stored in the flashback log itself. ERROR: Unable to verify the graphical display setup. If the database is managed by Oracle Clusterware, broker does not open any pluggable status before the crash. Keep this trigger as simple and reliable as possible, limiting it to only what is absolutely necessary at the moment of role transition, since any failures at this point may affect availability. automatic failover feature in configurations set up for zero data loss protection at any If these parameters are modified outside of Broker, it raises a warning. Improper Oracle Net configuration is a leading cause of reported FSFO issues. The default name for Required fields are marked *. The required attributes vary depending on your configuration (including whether your environment is Oracle RAC-based or single-instance). When the standby becomes available again, the primary and standby re-synchronize and resume synchronous redo transfer. Oracle Real Application Clusters Administration and Deployment Guide for more information about configuring FAN, FCF, and ONS on an Oracle Real Application Clusters (Oracle RAC) database. The mode can have one of the following values: DISABLED: Fast-start failover is disabled. FastStartFailoverAutoReinstate is set to FALSE, Another failover or switchover occurred after the fast-start failover completed but before the former primary database restarted, The master observer cannot connect to the former primary database, The former primary database cannot connect to the new primary database, The former primary database and the new primary database are not configured in the same fast-start failover environment, The former primary database was disabled because of a manual failover when fast-start failover was disabled. A high lag limit may lead to more data loss but may lessen the performance impact of the primary database. Initiate the failover on the standby database STAN: SQL>connect /@STAN as sysdba SQL> ALTER DATABASE RECOVER MANAGED STANDBY DATABASE FINISH; SQL> ALTER DATABASE COMMIT TO SWITCHOVER TO PRIMARY; 2. observers for a single Data Guard configuration. If a database must be re-created from a copy of the new primary database, it will have the following status: Re-create the standby database from a copy of the primary database and then reenable it, as described in How to Re-create and Reenable a Disabled Database. This configuration property establishes an acceptable limit, in seconds, that the standby is allowed to fall behind the primary in terms of redo applied, beyond which a fast-start failover will not be allowed. You can query the V$FS_FAILOVER_STATS view on the primary database to display statistics about fast-start failovers that have occurred on the system. 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 . operation. Presetting database properties related to redo transport services, such as LogXptMode, NetTimeout, StandbyArchiveLocation, StandbyAlternateLocation, and RedoRoutes. redo generation on the primary database will be stalled. If any errors occur during either conversion, the broker stops the switchover. Figure 6-2 shows the observer monitoring a fast-start failover configuration. 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. If this Oracle recommends that this property be set to a value that is small enough to allow timely detection of faults at the primary database, but large enough to limit the overhead associated with periodic observer connections to an acceptable level. created under this directory by DGMGRL will also have the same permissions. This nomination is noted in the observer log file and in the broker log file (drc*.log). If the observer is unable to regain a connection to the primary database within the specified time, then the observer begins a fast-start failover provided the standby database is ready to fail over. This feature increases the availability of your database in the event of a disaster by reducing the need for you to perform a failover operation manually. Log into the new primary and verify that the changes made it across. second. Setting this property to 'TRUE' (the default) causes the primary to self-terminate. Chapter 9 of the Data Guard Broker documentation (10g and 11g) contains a description of each property. collections and databases Set up replica sets and automatic failover in MongoDB Use sharding to scale horizontally, and learn how . STAN is now transitioned to the primary database role.Now your PHYSICAL STANDBY Database has become PRIMARY. 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. Displays the current fast-start failover mode. For example: Fast-start failover occurs if both the observer and the target standby database lose connection to the primary database for the period of time specified by the FastStartFailoverThreshold configuration property. disable fast-start failover with the FORCE option on the The drain_timeout is specified in the SRVCTL If fast-start failover is already enabled, the fsfocallout.ora. Add the SRLs. (Oracle Call Interface) client that connects to the primary and target standby databases It is possible to manually perform a completer failover to a standby database that receives redo data from a far sync instance. Choose a value high enough to avoid false disconnects from intermittent network trouble. Archiver is unable to archive a redo log because the device is full or unavailable. November 20, 2009. 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. issue commands and interact with the broker configuration. Initiate reinstatement by mounting the database. The information shown by this command is the same as that shown by a SHOW OBSERVER command on each individual configuration. This method will disable fast-start failover on all databases in the broker configuration. the location of the observer log file, and the location of the observer runtime data The Data Guard broker and the secondary database both run the observer and observe the primary database for downtime. While this eliminates the processing overhead associated with periodically establishing a new observer connection to the primary database, it also prevents the observer from detecting that it is not possible to create new connections to the primary database. 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. Let's run the command on the primary database to validate if the environments are ready for the role transition : JITPRD> alter database switchover to JITSDB verify; alter database switchover to JITSDB verify * ERROR at line 1: ORA-16475: succeeded with warnings, check alert log for more details 3. You can start the observer before or after you enable *PATCH v5 0/6] Add Toshiba Visconti Video Input Interface driver @ 2023-01-11 2:24 Yuji Ishikawa 2023-01-11 2:24 ` [PATCH v5 1/6] dt-bindings: media: platform: visconti: Add Toshiba Visconti Video Input Interface bindings Yuji Ishikawa ` (5 more replies) 0 siblings, 6 replies; 42+ messages in thread From: Yuji Ishikawa @ 2023-01-11 . If you don't already have a Flash Recovery Area (FRA), you will need to create one for Flashback Database. through these services to exit or for the specified wait time DGConnectIdentifier, "Scenario 9: Performing a Switchover Operation" for an example of using the VALIDATE DATABASE command to show a database's readiness to complete a role switchover, "Scenario 10: Performing a Manual Failover Operation" for an example of using the VALIDATE DATABASE command to show a database's readiness to complete a role failover. An observer process is integrated in the DGMGRL client-side component of the broker and typically runs on a different computer from the primary or standby databases and from the computer where you manage the broker configuration.
Thomas Watson Giovanni Father,
How Can Nationalism Eliminate An International Boundary Example,
Articles D