Oracle Restart is a subset of the RAC Cluster ware service -



The use of Grid Infrastructure is not limited to clusters—it also provides high availability to single-instance
Oracle deployments, as well. The standalone Grid Infrastructure installation was previously called Single
Instance High Availability (SIHA), but it was renamed to Oracle Restart in the public release. With Oracle
Restart, you shouldn’t need startup scripts to start and stop databases and services because oracle restart will take care.

The added benefit of using Oracle Restart (Grid Infrastructure) is the usage of Automatic Storage Management (ASM) is included.  


Oracle Restart is managed by CRSCTL utility and it uses Oracle High Availability Services to start and stop the components managed by Oracle Restart.

Restart controls the following resources.
• Database
• Listener
• ASM
• ASM Disk Group
• Oracle Notification Services

Another benefit: It
Doesn’t require the definition of an OCR or voting disk locations. The execution of the root.sh script
initializes the OLR and creates the ASM instance with the disk groups specified.


You can experiment with the functionality of Oracle Restart by just killing the Oracle PMON processes at the OS level. This will cause the instance failure and will take the database offline.
Before 11gr2 or even 11gr2 databases without restart, the restart will not happen automatically. A manual startup will have to be issued. But once Oracle Restart is used, the instance recovery will resume automatically and all services will be started to make database available again.

After installing Oracle Restart, you will see the following list of resources in your system:

--> there is no CRSD
--> In Comparison with the cluster start sequence of standard RAC you do not see a cssdmonitor process , rather cssdagent will have to monitor ocssd.bin .
--> OHAS daemon uses OLR to read resource configuration and dependencies
--> Oracle restart does not use a gpnp profile .
-->Once Oracle Restart is configured, you can add databases to it just as you do in RAC, but with one
important difference: no instances need to be registered.

Other Benefits
Integration with SQLP*PLUS, LNSRCTL
The best thing about the Oracle Restart is that it is tightly integrated with SQL*PLUS, LSNRCTL etc. So when you perform a shutdown of the database via SQL*PLUS, Oracle Restart realizes that it is deliberate command sent by DBA, so it won’t attempt to restart the database



Oracle Restart is deprecated in Oracle Database 12c. Oracle Restart is currently restricted to manage single-instance Oracle databases and Oracle ASM instances only, and is subject to desupport in future releases.


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