The first thing we need to understand is that Siebel Gateway Server is a LOGICAL Siebel server, and not a PHYSICAL Siebel server. Its primary purpose is to provide the services of a Name Server. It is for this reason that it is also referred to as a Siebel Gateway Name Server.

This server comes the highest in the hierarchy (there is actually no such thing, but good from understanding point of view), and can contain multiple Siebel Enterprise Servers within it.

A Siebel Gateway Server contains the following information within it:
Definitions & Information about the Siebel Server Component Groups and the Siebel Server Components
Connection Parameters & other connectivity information

It is the connectivity information it contains, which actually links Siebel Servers to the outside world, and allows us to access Siebel by just entering a URL. A Siebel Gateway Server interacts with the Web Server, which receives the actual HTTP requests.

There is an important file by the name of “siebns.dat” which houses all the information discussed above. The availability of various Siebel Components (both vanilla and custom) is saved here. The Server Components who need any resources from some other Server Components, then ask the Name Server for the Availability & Connectivity Information.

Setting up failover clusters is a common way of ensuring high availability Siebel Servers nowadays.

Related posts:

1. Siebel Server Architecture – an Introduction
2. Siebel Server Verification – EVT Tool
3. Siebel – Admin Mode Flag
4. Siebel Admin Mode Flag – II – Issue Log
5. Siebel – Deploying SRF without Server/OM Re-start!!!!