Proper tnsnames.ora management for Large Sites
Managing the tnsnames.ora file is one of the most challenging software distribution issues for an Oracle DBA.
In large shops, there may be thousands of PC Oracle clients, and each of these clients will need a working copy of the tnsnames.ora file.
Distribution of changes to the tnsnames.ora file to thousands of PC clients can be a very perplexing task for the DBA.
As we know, in a dynamic Oracle shop, the tnsnames.ora file may change frequently as new databases are added and older databases are dropped.
Hence, it can be quite a chore to ensure that every Oracle server and client has the most up-to-date copy of the tnsnames.ora file.
Some shops develop their own software distribution mechanism for this task, while others use third-party delivery software, such as Tivoli Courier.
In any case, the proper management of the tnsnames.ora file can be a real challenge for a large Oracle shop.
Oracle Net
Communication software that enables a network session from a client application to an Oracle database server. After a network session is established, Oracle Net acts as a data courier for the client application and the database server. It is responsible for establishing and maintaining the connection between the client application and database server, as well as exchanging messages between them. Oracle Net is able to
perform these jobs because it is located on each computer in the network.
Oracle Net Configuration Assistant
A postinstallation tool that configures basic network components after installation,
including:
- Listener names and protocol addresses
- Naming methods the client uses to resolve connect identifiers
- Net service names in a tnsnames.ora file
- Directory server usage
Oracle Names (Legacy)
Oracle Names was a product that stored connection information about all databases in a distributed environment at a single location.
Any time an application issues a connection request, it consulted the Oracle Names repository to determine the location of the database server.
Oracle Names was primarily an administrative aid that made the maintenance of the information easier.
Its use was not required and the alternative was to provide local tnsnames.ora files on every client machine.
Note: In future releases, Oracle Names will not be supported as a centralized naming method. Since no new enhancements are being added to Oracle Names,
- use directory naming or
- migrate an existing Oracle Names configuration to directory naming.