Why is the service already made?

Question

Hi,
I have successfully installed RAC on two OEL servers with a NFS server. Surprisingly, after the installation I get the service already started.
1) lsnrctl status
service "MY-DB" has 2 instance(s) ...
2) Just take look the listener.ora
LLISTENER_NODE1 = (...) and nothing more.
3) But in the tnsnames.ora, I see the following,
LLISTENER_MY-DB =(...)
MY-DB = (...)
4) srvctl status service MY-DB
nothing retures.
My question is why the service MY-DB already is started, if I do: lsnrctl status?

Answer 1

Your database is called MY-DB?
Oracle creates service for the database name and services for the instance names in the cluster. At a minimum they are required for a user to make connection. However these services are not application services. that is why you don't see them using SRVCTL. Application services defined using DBCA or srvctl utility are only visible as services in DBCA. As a best practice you should define such services and should be used for users or clients connecting to the database.
if you connect using SQLPLUS and check the parameter SERVICE_NAME you will notice that the database name is registered as the default service. Thia is why it gets registered with the listener dynamically. This is required do not remove this definition.