Causes of Data Loss Source: Disaster Recovery Journal Hardware & system errors Natural disasters 3% Software corruption 4% Computer viruses 7% Human errors 36% 49%
Real Application Clusters Continuous Availability for all Applications Data Guard Guaranteed Zero Data Loss Flashback Guaranteed Zero Data Loss Dynamic Reconfiguration Capacity on Demand without Interruption Online Redefinition Adapt to Change Online ASM Mirroring Storage Failure Protection Human Error Site Failures Storage/Net Failures Unplanned Downtime System Failures System Maintenance Planned Downtime Database Maintenance
What is a Standby Database ?
A copy of a production database that you can use for disaster protection. You can update the standby database with redo logs from the production database in order to keep it current. If a disaster destroys the production database, you can activate the standby database and make it the new production database.
You can maintain the standby data in one of the following modes:
For physical standby databases
For logical standby databases
A Standby Database is NOT Data Guard
Why Data Guard?
Data Guard helps you protect your Data.
Takes your data and automatically puts it elsewhere
Makes it available for Failover in case of failure.
The apply process also revalidates the log records to prevent application of any log corruptions
Geographically dispersed sites
Useful for logical data corruptions if lag behind used
Flexible configuration options for protection level
Reporting and backups can be diverted to standby
Automatic resync for failed primary
Switchover for Maintenance
Traditional Physical Standby Databases Investment in Disaster Recovery
Active Data Guard 11 g Investment in Improved Quality of Service
Data Guard 11g has several options for deploying different CPU architectures, O.S. binaries and Oracle database binaries, on primary and standby systems.
For example, the primary database may be on Windows, and the standby database may be on Linux.
See MetaLink Note 413484.1 for latest capabilities and restrictions