Automate the Application's Tear-down

This chapter explains why an Application’s Tear-down should be automated alongside its Build and Deployment.

Why Automate Tear-down

When Deployment is automated but Tear-down is not, environments accumulate leftover components, and rebuilding an Instance from scratch becomes risky because no one is sure what a clean environment looks like. Automating Tear-down makes removal as reliable as installation, makes it safe to tear down and rebuild test environments frequently, and ensures that Decommissioned Instances are removed completely when their time comes.

Establish Tear-down Automation

Automate, to the greatest degree feasible, the removal of versions and Instances, including the infrastructure, accounts, network rules, certificates, monitoring, and references in other Systems described in the previous chapter, together with the verification that removal is complete. Build Tear-down into the same automation that builds and deploys the Application, and, where infrastructure is defined as code, use that code to remove what it created. Require explicit approval before automation tears down Production or Decommissioned Instances, and ensure that data retention rules are applied before any data is destroyed.

Document and Share the Automation

Record the Tear-down automation, its triggers, approvals, safeguards, and owners in the Application Documentation, and link to its definitions in the Application’s repositories. Record any steps that remain manual, with their justification.

Best Practice: Automate the Application’s Tear-down

It is a best practice to both establish and document the solution for removing an Application cleanly: automate the Tear-down of versions and Instances alongside Build and Deployment, with verification, approval safeguards for Production and Decommissioned Instances, and data retention rules applied first.

Benefits: Automated Tear-down makes environments disposable and reproducible, which speeds up testing and reduces cost. Its approval safeguards and retention checks ensure that this speed never comes at the expense of accidentally destroying a Production Instance or data the enterprise is obliged to keep.

Connections to Related IF4IT Practices and Inventories

The IT Operating Environments Best Practices addresses automating environment construction, reconstruction, and destruction.