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Dear all,
Reading 6. Configuring Naming Methods, Net8 Administrator's Guide Release 8.1.6, the service_name is explained as follows:
<quote begin>
Understanding Connect Descriptors
A connect descriptor is comprised of one or more protocol addresses of
the listener and connect data information for the destination service.
The following example shows a typical connect descriptor:
sales=
(description=
(address= (protocol=tcp)(host=sales-server)(port=1521))
(connect_data=
(service_name=sales.us.acme.com)))
The ADDRESS portion contains the listener protocol address, and the CONNECT_DATA portion contains the destination service information. In this example, the destination service is a database service named sales.us.acme.com.
When creating a connect descriptor for an Oracle release 8.1 database service, you must identify the service with the SERVICE_NAME parameter. Optionally, you may identify an instance with the INSTANCE_NAME parameter, as shown in the following:
sales=
(description=
(address= (protocol=tcp)(host=sales-server)(port=1521))
(connect_data=
(service_name=sales.us.acme.com) (instance_name=sales)))
The values for these parameters come from the SERVICE_NAMES (with an
S) and INSTANCE_NAME parameters in the initialization parameter file.
The SERVICE_NAMES parameter in the initialization parameter file is
typically the global database name, a name comprised of the database
name and domain name, entered during installation or database
creation. For example, sales.us.acme.com has a database name of sales
and a domain of us.acme.com. The INSTANCE_NAME parameter in the
initialization parameter file is defaulted to the SID entered during
installation or database creation.
<quote end>
I have two questions:
1.In this section, the service_name in tnsnames.ora comes from
SERVICE_NAMES init.ora parameter. However, in real test, the
service_name in tnsnames.ora has to match global_dbname in
listener.ora, not init.ora parameters. I am confused why it says so.
2.Here instance_name and SID are distinguished. I want to confirm that
SID is something stored in the control files, and instance_name is
something configured in tnsnames.ora, init.ora, environment variables
or registry entries, and these two parties have to match each other.
Your comments are appreciated.
Dino Received on Thu Oct 11 2001 - 21:29:41 CDT