Server Roles in a MOSS Farm

The architecture of a MOSS farm may contain one or more servers. These servers have various roles which can be divided into three broad categories, Web Front End (WFE), application server and database server.

1. Web Front End (WFE) Servers
The fast and lightweight WFE servers interact with the user. The MOSS site is hosted on the IIS installation on WFE. These servers connect to the database servers to query the MOSS database for grabbing the requested content and rendering the results in the client browser. All WFEs in a farm must be identical and may be load balanced.

2. Application Servers
An application server provides all shared service level capabilities to the users through WFEs.Just like WFEs, load balancing can be implemented on the application servers too. Following are some examples of the shared services hosted on an application server:

• Search Indexing
• Search Query
• Excel Calculation Service
• Windows SharePoint Services Search

3. Database Servers
The database server has the maximum impact on the availability of the MOSS solution because it is the single point of data storage for all MOSS data (users, applications and configurations). Redundancy and high availability can be ensured by clustering or mirroring.