• Describes the options for restoring data faults • use the new RMAN data repair command to perform the following operations: -List faults-receive repair suggestions-repair faults • Perform preventive fault checks • query the data recovery guidance View
• Data Guard provides failover to the standby database so that the operation is not affected by the downtime. • Data Recovery guide is a new feature of Oracle Database 11g. It analyzes faults based on fault phenomena and determines the repair policy: -combine multiple faults for effective repair-provide a suggested Repair Option-Perform Repair as required • flash back the lifecycle of the Technical Protection Line and help fix logical problems. A data fault rectification "data fault" refers to missing, damaged, or inconsistent data, logs, controls, or other files, which cannot be accessed by Oracle instances. When a database encounters a problem, it usually takes most of the downtime to analyze the basic cause and select the correct solution. Oracle Database 11g provides several new and enhanced tools to analyze and fix Database problems. • Data Guard allows you to failover to the slave database (with your own Data copies), so that you can continue operations in the event of a Data failure in the master database. In this way, after the fault is transferred to the standby database, the faulty database (the old primary database) can be repaired without worrying about its impact on the application. Data Guard has many improvements. • Data Recovery Guidance is a built-in tool that automatically diagnoses data faults and reports corresponding repair options. For example, if the data recovery guide finds that there are many damaged blocks, it is recommended that you restore the entire file instead of repairing these blocks separately. Therefore, it helps you perform correct troubleshooting. You can manually repair data faults, or request data recovery instructions to perform repairs for you to shorten the fault recovery time. You can use the flash back technology to fix logical problems. • Flash back archive allows you to maintain continuous changes to table data within a specified period of time so that you can access archive data. • Flashback transaction processing allows you to roll back transaction processing and all conflicting transactions with one click. You have learned the following information: • Automatic Recovery of data file media by RMAN (a common form of recovery to avoid logical and physical faults) and block media recovery (recover a single block instead of the entire data file ). • Automatic Storage Management (ASM) can prevent storage faults.
• Rapid detection, analysis and repair of faults • minimal interference to users • Repair of faults during downtime and runtime faults • user interface provided: -em gui interface-(multiple paths)-RMAN command line • Supported Database Configuration:-single instance-non-RAC-support failover to slave database, however, it does not support analysis and restoration of backup database data recovery guidance function data recovery guidance will automatically collect data fault information when an error occurs. In addition, it can check faults in advance. In this mode, it can detect and analyze data faults before the database process detects corruption and sends error messages (note that repair is always done under human control ). Data faults may be very serious. For example, if the latest log file is missing, the database cannot be started. Some data faults (such as block damages in data files) are not catastrophic because they do not stop the database or prevent you from starting an Oracle instance. The data recovery guide can handle either of the following situations: you cannot start the database (because necessary database files are missing or these database files are inconsistent or damaged ), another situation is that the file is damaged during the running. The first choice for solving serious Data faults is to first transfer the fault to the standby database (provided that the fault is configured under Data Guard), so that the user can restore the connection as soon as possible. The primary cause of Data failure needs to be repaired, but fortunately, this operation will not affect users. The user interface provides data recovery guidance from Enterprise Manager (EM) Database Control and Grid Control. When a fault exists, there are several methods to access data recovery guidance. The following examples start from the "Database Instance" homepage: • "Availability" tab page> Perform Recover> Advise and Recover (recommended and restored) • Link to "Active Incidents"> "Problems" page of "Support Workbench": "Checker Findings (check result) "tab page> Launch Recovery Advisor (BOOT Recovery guide) • Database Instance Health (Database Instance Health status)> click a specific link, for example," Incidents (unexpected events) "ORA 1578>" Support Workbench "on the" Problems Detail "Page> Data Recove Ry Advisor (data recovery guide) • Database Instance Health (Database Instance Health status)> "Related Links" section: Support Workbench> on the Checker Findings tab page, click Launch Recovery Advisor. • Link: Advisor Central> Advisors) "tab page:" Data Recovery Advisor (Data Recovery guide) "• Link: Advisor Central (Guide Center)>" Checkers "tab page: Details (Details)> run Detail tab: Launch Recovery Advisor can also be used through RMAN command lines. For example: rman target/nocatalogrman> list failure all; supported database configuration in the current version, data recovery guidance supports a single instance database, does not support Oracle Real Application Clusters (RAC) database. Data Recovery Guidance cannot use blocks or files transferred from the standby database to repair faults in the primary database. At the same time, you cannot use data recovery to guide the diagnosis and repair of faults in the backup database. However, data recovery guidance as a repair option does support failover to the standby database (as described above ).For more details, please continue to read the highlights on the next page:
Recommended reading:
Use the Duplicate function of RMAN to create a physical partition uard
Basic Oracle tutorial-copying a database through RMAN
Reference for RMAN backup policy formulation
RMAN backup learning notes
Oracle Database Backup encryption RMAN Encryption
Use RMAN to back up duplicate to create a replica uard
