What is a staging environment?

[burns]

On Tue, 2003-08-19 at 03:41, James McDonald wrote:

> What is a staging environment? I haven't heard of it before in relation 
> to IT.

Proper, enterprise class infrastructures don't do everything on their
main (live) systems. Believe it or not, industry 'best practices' call
for several duplicate (or near duplicate) environments. These are:

1) Development - a limited scale and scope environment sufficient to
allow developers to develop and do preliminary code testing on new
releases and patches. Development environment have broad (not detailed)
similarity to portions of the end-state build/architecture. 

2) Test - An environment for formal testing along specific lines as part
of the software release cycle (e.g. Test Cases, User Acceptance Testing,
etc.) Test environments are expected to be able to replicate certain
specified architectural conditions related to the end-state build.

3) Staging - Staging environments should be exact replicas, down to and
including software releases and patches, of the production (end-state)
build. In the staging environment, all proposed changes, patches new
releases, etc. are loaded and run under operating conditions to
determine optimal configurations and to see what, if anything, will
break or glitch. Often, staging environments also can serve a dual
purpose as an emergency "cold" backup system.

4) Production - this is the live, running end-state system. 

On enterprise architectures, each of these environments will consists of
numerous servers, routers, switches, storage arrays, etc. System service
time means dollars and IT managers hate to have a production system
taken down for any reason. Thus, having multiple environments such as
those described above can actually make sense in certain large scale
enterprises.
-- 
burns