Oracle DBA

When a database is originally created with the Global Database Name <database>, its db_name and db_unique_name are the same. The CRS (Cluster Ready Services) database resource is named as ora.<database>.db. Changing the db_unique_name involves a complete database restart and requires careful coordination of steps.

Step 1: Remove the Database, Instance, and Service Resources from CRS

$ srvctl stop database -d <database>
$ srvctl remove database -d <database>

Step 2: Start the Database and Change the DB_UNIQUE_NAME

Start the database:

SQL> STARTUP;

Change the db_unique_name and, if required, update the db_domain:

SQL> ALTER SYSTEM SET db_unique_name=<database>_test SCOPE=SPFILE SID='*';
SQL> ALTER SYSTEM SET db_domain=<domain> SCOPE=SPFILE SID='*';  

Rename the Global Database Name:

SQL> ALTER DATABASE RENAME GLOBAL_NAME TO <database>_test.<domain>;

Step 3: Add the Database Resource to the Cluster

Add the database resource:

$ srvctl add database -d _test -n -o

Add the instances:

$ srvctl add instance -d <database>_test -i <instance1> -n <node1>
$ srvctl add instance -d <database>_test -i <instance2> -n <node2>

Step 4: Create Dependencies Between Database and ASM

Ensure the database starts only after the ASM instance is running.

$ srvctl modify database -d <db_unique_name> -a "<diskgroup_list>"

Step 5: Add Database Services

Create database services with both instances as preferred.

$ srvctl add service -d <database>_test -s <service> -r "<instance1>,<instance2>"

Ensure you have adequate downtime for the process as it involves restarting the database.

Validate all changes thoroughly to ensure smooth functioning of the RAC environment after the change.