What IT Environments are Needed?

A great write-up by a third party articulating the different environments needed for a mature IT shop. What i think is missing here is Production FIX. This is the environment you develop / test in when the main environments have the next version of IT infrastructure, configurations or software.

There are typically three different environments in IT which have different roles. They tend to reflect the importance of that application/system to the end users.

1. Test/Development - used for the application developers to test their application code or new layered applications - they might have administration rights to the Windows/Linux servers in this environment.
2. Staging/UAT (User Acceptance Testing) - used for functional testing, should ideally be a replication of production. Once my code has been validated, it’s pushed to staging so that I can carry out due diligence and functional testing before I put the code/application into production. Access should be restricted so that code is validated in near production conditions.
3. Production - business affecting or user affecting systems, an outage therefore on these systems might damage our reputation or cause loss of revenue. Administration and security should be restricted in order to protect data and system reliability.

The idea is that by having the different operating environments you can limit any infrastructure or application failures through adequate testing which may include performance load testing.

[From What’s UAT then?]