DevOps · Flashcard
What is a Dockerfile?
- AA text file containing ordered instructions that Docker reads to automatically build an image layer by layer
- BA YAML configuration file that defines multiple services, networks, and volumes for a multi-container application
- CA binary manifest embedded inside every Docker image that records metadata about the build environment used
- DA shell script that Docker executes inside a running container to install packages and configure the application
Why this is the answer
Each instruction (FROM, RUN, COPY, etc.) creates a new layer in the image. Docker executes them sequentially, caching unchanged layers to speed up subsequent builds.
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