How can you override a command that will be executed in a container of a specific service in Docker Compose?
Experience Level: Senior
Tags: Docker Compose
Answer
You can do this by modifying the entrypoint: property of your service.
version: "3.9"
services:
my-service:
image: busybox
entrypoint: ["/bin/sh", "-c", "sleep 1d"]
Setting entrypoint both overrides any default entrypoint set on the service’s image with the ENTRYPOINT Dockerfile instruction, and clears out any default command on the image - meaning that if there’s a CMD instruction in the Dockerfile, it is ignored.
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