Database service is used to manage a workload in a database. From the client side, users connect to the service, not to the database and the service forwards the connection to the appropriate and least loaded instance. Each service is assigned to the instance that is known as a preferred instance. When the preferred instance fails, Oracle automatically move the service to the surviving instance known as available instance.
Q1. Create a new service, add a new TNS entry that uses the new service, connect to the database with using a new TNS entry, check the instance name, shutdown the connected instance from the different terminal and check the connection again. The session should failover to the second instance. (15min)
1. Create a new service, and check this.
/* -r: comma separated list of preferred instances. Instance "racdb1" is preferred than racdb2 */
srvctl add service -db RACDB -service SERVICE01 -r racdb1,racdb2
srvctl start service -db RACDB -service SERVICE01
srvctl config service -db RACDB -service SERVICE01
2. Add a new TNS entry that uses the new service.
sqlplus system/asdf0930k@THENEWSERVICE
show parameter instance;
shutdown abort;
show parameter instance;
startup force;
Q2. Create a new pool using MIN_SIZE, MAX_SIZE and IMPORTANCE parameters. Create a child pool based on the first pool (8min)
When a service is defined for the policy managed database, the service is assigned to the server pool. Server pool can be defined as UNIFORM or SINGLETON.
srvctl config serverpool
crsctl status serverpool -p
crsctl add serverpool ~
