FR-IMG-003 — Immutable Infrastructure Workflows

Go to Crucible Image Management Requirements

Statement

Crucible SHALL apply changes to deployed images by replacing the images rather than modifying them in place.

Derived From

This requirement derives from:

Crucible System Requirements Specification, Version 1.1 Draft, Functional Requirements, FR-IMG-003The Original Requirement states:

The system shall support immutable infrastructure workflows.[C1]

FR-IMG-003:

Replaces The system with the defined system name CrucibleChanges shall to the established uppercase normative form SHALLReplaces the weak verb support with the observable behavior applyExpresses immutable image management as replacement rather than in-place modification

Rationale

An immutable infrastructure workflow applies a change by replacing a deployed image with a newly built image rather than modifying the deployed image in place.

Replacement preserves the relationship between a deployed subject and the image Artifact from which the subject was created.

This approach reduces configuration drift and supports repeatable deployment of Machine Images and Container Images.

Applies To

This requirement applies to:

Deployed imagesImage replacement operations

Verification

Verification confirms that:

A change to a tested deployed image produces a replacement imageCrucible replaces the tested deployed image with the replacement imageCrucible does not apply the tested change by modifying the deployed image in placeThe replacement image can be identified as distinct from the image it replaces

Referenced By

The following pages reference this requirement:

Implementation Status

Implemented and Verified

Requirement Status

Issues

Notes for Editors

This requirement page retains the stable requirement identifier FR-IMG-003.

This page is a leaf requirement page and omits a trailing :start from its namespace.

The Statement preserves the approved source intent by requiring image changes to use replacement rather than in-place modification.

Do not add image building, signing, verification, promotion, deployment validation, rollback, or recovery obligations to the Statement unless the controlling requirement changes through an approved requirements process.

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