How is Compose different from a Dockerfile?
A Dockerfile is an instruction for how to build an image. It describes what should be inside the container: packages, dependencies, files, build and run commands.
Docker Compose is a tool for how to run several containers together, configuring their links, ports, volumes, environment variables, and so on. It uses already-built images (including ones built from a Dockerfile).
In short:
| Question | Dockerfile | Docker Compose |
|---|---|---|
| Task | Build an image | Run and orchestrate several containers |
| Format | Instructions for creating an environment | Description of services, networks, and volumes |
| Level | One container | Several services as one system |
The usual pairing is:
Dockerfile creates the image → docker-compose.yml starts the needed number of containers, links them, and brings up the whole environment with one command.
Short Answer
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