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Siebel Gateway Name Server

The Siebel Gateway Name Server is a logical entity, not a physical server consisting of a Name Server.

The name server is the primary service of the Siebel Gateway Name Server, which coordinates the Siebel Enterprise Server and Siebel Servers. A single Siebel Gateway Name Server can now support multiple Siebel Enterprise Servers.

About Name Server

The Name Server provides the persistent backing of Siebel Enterprise Server configuration information, including:

• Definitions and assignments of component groups and components
• Operational parameters
• Connectivity information

As this information changes—such as during the installation or configuration of a Siebel Server—it is written to the siebns.dat file on the Name Server. At startup, the Siebel Server obtains its configuration information from the Name Server's siebns.dat file. For further information on this file, see Backing Up the Siebel Gateway Name Server Data.

The Name Server also serves as the dynamic registry for Siebel Server and component availability information. At startup, a Siebel Server within the Siebel Enterprise Server notifies the Name Server of its availability and stores its connectivity information—such as network addresses—in the Name Server's nonpersistent (volatile) store. Periodically, the Name Server also flushes its current state to the siebns.dat file.

Enterprise components (including the Server Manager) query the Name Server for Siebel Server availability and connectivity information. When a Siebel Server shuts down, this information is cleared from the Name Server.

In a Windows environment, the Name Server runs as a Windows service. In a UNIX environment, the Name Server runs as a daemon process. The system process associated with the Siebel Gateway Name Server is siebsvc.exe. Each running Siebel Server has a corresponding Siebel Gateway Name Server system process.

A single Name Server can potentially serve several databases in an environment (such as multiple development and test environments). For purposes of mitigating dependencies and improving recoverability, you should keep the Siebel production environment separate from other Siebel environments (development or test) by using a separate Name Server.

If you decide to maintain multiple development or test environments on one Name Server, make sure that you use a distinct Siebel Enterprise Server for each table owner (or database for SQL server platforms).

NOTE:  Do not maintain the development, test, and production environments on the same Name Server.

You can specify and create a new Siebel Enterprise Server when you install the first Siebel Server for a table owner or database.

NOTE:  In a Windows environment, there can be only one Name Server installed per machine.

Impact of Failure

When the Name Server goes down, service to active user connections is not immediately interrupted. All Siebel Server components and object managers currently running continue to do so. However, no new Siebel Server components can be started or added. Server administration functions become limited.

High-Availability Solution for Name Server

Siebel Business Applications supports a number of server clustering technologies that are platform-specific to achieve high availability for the Name Server. For information on server clustering, see the Deployment Planning Guide.

Resource Requirements for Name Server

The Name Server requires very few system resources. Follow the hardware recommendations listed in System Requirements and Supported Platforms on Siebel SupportWeb.