Environments

When developing and maintaining software, you'll need several environments. Usually you'll need at least four environments, each servering a different purpose:

  • Dev (development)
    • Developers have free rein (admin) to do whatever they need to for development, such as install software for evaluation, test new architecures, or test production install instructions.
    • Code changes from development will most likely create new test builds.
    • The development system is able to run the entire application(s) locally (The Entire Application Runs Locally in Development).
  • Test
    • Developers combine code from everyone and test to ensure they merged correctly and it works as expected.
    • Builds that pass in test can be passed to staging for possible use in production.
  • Staging
    • Permissions and data are exact copies from production.
    • Data is updated on some predefined schedule determined by communication between developers and system administrators.
    • End users and other testers verify bug fixes and new features.
    • Any build that passes in staging is eligible for promotion to production.
  • Prod (production)
    • This is where built software is deployed for use by all users.
    • Actual data is entered, and software provides value.
    • Developers have as little admin access as needed.
    • Production also has a well defined process for deploying new test builds that have been promoted. See the Build Promotion section.

Note: Most (if not all) environments will need the full set of developer tools. Also, each environment should be sandboxed from each other to prevent resources from accidents.

Monitoring

Applications mysteriously failing? Disks have filled to capacity for the 100th time? Everything is working...just VERY SLOWLY? Etc. There is a whole host of problems (bugs) that are difficult or impossible to find without good comprehensive monitoring of the environments. A good starting point would be O'Reilly's The Monitoring Infrastructure Is Critical which lists lots of tools that can help with this ongoing problem.