The 3-server configuration provides good separation between the servers to minimize spikes in performance: one server each is dedicated to the database, the iMIS application, and the Public web site, which communicates only with the iMIS database. This way, a performance issue on one server stays isolated to that server function. However, the added cost for additional servers and maintenance generally makes sense only for larger implementations.
Benefits
■ Even and manageable performance
■ Good redundancy
Considerations
■ No failover (such as no multiple Public sites or iMIS databases)

Database server on one host, a iMIS appserver with support for Desktop and web clients on a 2nd host, and a iMIS appserver with support only for the Public view on a 3rd host
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Examples |
Appserver |
Database server |
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Medium |
□ 4 GB of RAM □ 2.8 GHz Dual Core Pentium or Celeron CPU □ 250 GB hard drive w/ 200 GB free |
□ 6-8 GB of RAM □ 2.33 GHz Quad Core Xeon CPU, 1333MHz FSB □ 250 GB hard drive w/ 200 GB free |
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Large |
□ 4 GB of RAM □ 2.8 GHz Dual Core Pentium or Celeron CPU □ 250 GB hard drive w/ 200 GB free |
□ 12-16 GB of RAM □ Dual 2.33 GHz Quad Core Xeon CPU, 1333MHz FSB □ 2 - 500 GB hard drive w/ 450 GB free |