Server farm environments can encompass a wide range of topologies, and can include many servers or as few as two servers commercially. To deploy a high-availability solution, you must deploy a server farm. By using a server farm, you mitigate against the effects of unexpected downtime as well as downtime that is related to ongoing maintenance, such as operating system updates.
There are several different server topologies that can be used as a baseline. Each of these topologies builds in a level of server redundancy.
This following provides an overview of these server farms.
Small Server Farm
A small server farm typically consists of a database server running either Microsoft SQL Server 2005 or Microsoft SQL Server 2000 with the most recent service pack, and one or more servers running Internet Information Services (IIS) and Office SharePoint Server 2007. In this configuration, the front-end servers are configured as Web servers and application servers. The Web server role provides Web content to clients. The application server role provides Office SharePoint Server 2007 services such as servicing search queries, and crawling and indexing content.
Medium Server Farm
A medium server farm typically consists of a database server, an application server running Office SharePoint Server 2007, and one or two front-end Web servers running Office SharePoint Server 2007 and IIS. In this configuration, the application server provides indexing services and Excel Calculation Services, and the front-end Web servers service search queries and provide Web content.
Large Server Farm
A large server farm typically consists of two or more clustered database servers, several load-balanced front-end Web servers running Office SharePoint Server 2007, and two or more application servers running Office SharePoint Server 2007. In this configuration, each of the application servers provides specific Office SharePoint Server 2007 services such as indexing or Excel Calculation Services, and the front-end servers provide Web content.
Development Environments
For Development purposes you could install MOSS on a single server with all 3 tiers (Front End, Application Services, Database) shared on this server, to allow developers to develop custom soultions.
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