4 Oracle Database High Availability Solutions for Unplanned Downtime
Oracle Database offers an integrated suite of high availability solutions that increase availability.
These solutions also eliminate or minimize both planned and unplanned downtime, and help enterprises maintain business continuity 24 hours a day, 7 days a week. However, Oracle's high availability solutions not only go beyond reducing downtime, but also help to improve overall performance, scalability, and manageability.
- Outage Types and Oracle High Availability Solutions for Unplanned Downtime
Various Oracle MAA high availability solutions for unplanned downtime are described here in an easy to navigate matrix. - Managing Unplanned Outages for MAA Reference Architectures and Multitenant Architectures
High availability solutions in each of the MAA service-level tiers for the MAA reference architectures and multitenant architectures are described in an easy to navigate matrix.
Parent topic: Oracle Database High Availability Overview
Outage Types and Oracle High Availability Solutions for Unplanned Downtime
Various Oracle MAA high availability solutions for unplanned downtime are described here in an easy to navigate matrix.
The following table shows how the features discussed in the referenced (hyperlinked) sections can be used to address various causes of unplanned downtime. Where several Oracle solutions are listed, the MAA recommended solution is indicated in the Oracle MAA Solution column.
Table 4-1 Outage Types and Oracle High Availability Solutions for Unplanned Downtime
Outage Scope | Oracle MAA Solution | Benefits |
---|---|---|
Site failures |
Oracle Data Guard and Continuous Application Service (MAA recommended) |
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Recovery Manager, Zero Data Loss Recovery Appliance and Oracle Secure Backup |
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Instance or computer failures |
Oracle Real Application Clusters and Oracle Clusterware and Continuous Application Service (MAA recommended) |
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Storage failures |
Oracle Automatic Storage Management (MAA recommended) |
Mirroring and online automatic rebalancing places redundant copies of the data in separate failure groups. |
Oracle Data Guard (MAA recommended) |
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|
Recovery Manager with Fast Recovery Area, and Zero Data Loss Recovery Appliance (MAA recommended) |
Fully managed database recovery and managed disk and tape backups |
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Data corruption |
Corruption Prevention, Detection, and Repair (MAA recommended) Database initialization settings such as
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Different levels of data and redo block corruption prevention and detection at the database level |
Data corruption |
Oracle Data Guard (MAA recommended) Oracle Active Data Guard Automatic Block Repair
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Dbverify, Analyze, Data Recovery Advisor and Recovery Manager, Zero Data Loss Recovery Appliance, and ASM Scrub with Fast Recovery Area (MAA recommended) |
These tools allow the administrator to execute manual checks to help detect and potentially repair from various data corruptions.
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Data corruption |
Oracle Exadata Database Machine and Oracle Automatic Storage Management (MAA recommended) DIX + T10 DIF Extensions (MAA recommended where applicable) |
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Human errors |
Oracle security features (MAA recommended) |
Restrict access to prevent human errors |
Oracle Flashback Technology (MAA recommended) |
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Delays or slow downs |
Oracle Database and Oracle Enterprise Manager Oracle Data Guard (MAA recommended) and Continuous Application Service |
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File system data |
Enables full stack failover that includes non-database files |
Managing Unplanned Outages for MAA Reference Architectures and Multitenant Architectures
High availability solutions in each of the MAA service-level tiers for the MAA reference architectures and multitenant architectures are described in an easy to navigate matrix.
If you are managing many databases in DBaaS, we recommend using the MAA tiers and Oracle Multitenant as described in Oracle MAA Reference Architectures.
The following table identifies various unplanned outages that can impact a database in a multitenant architecture. It also identifies the Oracle high availability solution to address that outage that is available in each of the MAA reference architectures.
Table 4-2 Unplanned Outage Matrix for MAA Reference Architectures and Multitenant Architectures
Event | Solutions by MAA Architecture | Recovery Window (RTO) | Data Loss (RPO) |
---|---|---|---|
Instance Failure |
BRONZE: Oracle Restart |
Minutes if instance can restart |
Zero |
SILVER: Oracle RAC (see Oracle Real Application Clusters and Oracle Clusterware) or Oracle RAC One Node, and Continuous Application Service |
Seconds with Oracle RAC, minutes with Oracle RAC One Node |
Zero |
|
GOLD: Oracle RAC (see Oracle Real Application Clusters and Oracle Clusterware and Continuous Application Service |
Seconds |
Zero |
|
PLATINUM: Oracle RAC (see Oracle Real Application Clusters and Oracle Clusterware) and Continuous Application Service |
Zero Application Outage |
Zero |
|
Permanent Node Failure (but storage available) |
BRONZE: Restore and recover |
Hours to Day |
Zero |
SILVER: Oracle RAC (see Oracle Real Application Clusters and Oracle Clusterware) and Continuous Application Service |
Seconds |
Zero |
|
SILVER: Oracle RAC One Node and Continuous Application Service |
Minutes |
Zero |
|
GOLD: Oracle RAC (see Oracle Real Application Clusters and Oracle Clusterware) and Continuous Application Service |
Seconds |
Zero |
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PLATINUM: Oracle RAC (see Oracle Real Application Clusters and Oracle Clusterware) and Continuous Application Service |
Seconds |
Zero |
|
Storage Failure |
Zero downtime |
Zero |
|
Data corruptions |
BRONZE/SILVER: Basic protection Some corruptions require recover restore and recovery of pluggable database (PDB), entire multitenant container database (CDB) or non-container database (non-CDB) |
Hour to Days |
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GOLD: Comprehensive corruption protection and Auto Block Repair with Oracle Active Data Guard |
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Zero unless corruption due to lost writes |
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PLATINUM: Comprehensive corruption protection and Auto Block Repair with Oracle Active Data Guard Oracle GoldenGate replica with custom application failover |
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Zero when using Active Data Guard Fast-Start Failover and Oracle GoldenGate |
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Human error |
ALL: Logical failures resolved by flashback drop, flashback table, flashback transaction, flashback query flashback pluggable database, and undo. |
Dependent on detection time but isolated to PDB and applications using those objects. |
Dependent on logical failure |
All: Comprehensive logical failures impacting an entire database and PDB that requires RMAN point in time recovery (PDB) or flashback pluggable database |
Dependent on detection time |
Dependent on logical failure |
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Database unusable, system, site or storage failures, wide spread corruptions or disasters |
BRONZE/SILVER: Restore and recover |
Hours to Days |
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GOLD: Active Data Guard Fast-Start Failover and Continuous Application Service |
Seconds |
Zero to Near Zero |
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PLATINUM: Oracle GoldenGate replica with custom application failover |
Zero |
Zero when using Active Data Guard Fast-Start Failover and Oracle GoldenGate |
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Performance Degradation |
ALL: Oracle Enterprise Manager for monitoring and detection, Database Resource Management for Resource Limits and ongoing Performance Tuning |
No downtime but degraded service |
Zero |