Siebel System Administration Guide > Siebel Enterprise Server Architecture >

About Siebel Gateway Name Server

The Siebel Gateway Name Server coordinates the Siebel Enterprise Server and Siebel Servers. A single Siebel Gateway Name Server can support multiple Siebel Enterprise Servers. The Siebel Gateway Name Server also 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 Siebel Gateway Name Server. At startup, the Siebel Server obtains its configuration information from the Siebel Gateway Name Server's siebns.dat file. For further information on this file, see Backing Up the Siebel Gateway Name Server Data.

The Siebel Gateway 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 Siebel Gateway Name Server of its availability and stores its connectivity information- such as network addresses-in the Siebel Gateway Name Server's non-persistent (volatile) store. Periodically, the Siebel Gateway Name Server also flushes its current state to the siebns.dat file.

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

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

A single Siebel Gateway 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 Siebel Gateway Name Server.

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

NOTE:  In a Windows environment, there can be only one Siebel Gateway Name Server installed on each machine.

Impact of Failure

When the Siebel Gateway 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 Siebel Gateway Name Server

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

Resource Requirements for Siebel Gateway Name Server

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