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CompTIA Cloud+ CV0-004 · Domain 5: DevOps fundamentals

Container images, registries, tagging and promoting one build through environments

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Last reviewed September 25, 2026 · Leer en español

A container image is a read-only package containing an application, its runtime, libraries and configuration defaults, built in layers from a Dockerfile or similar build file. Each instruction, such as copying files or installing packages, creates a layer; layers are cached and shared between images, which speeds builds and saves storage.

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