What is the RUN instruction good for in Docker?
Experience Level: Senior
Tags: Docker
Answer
The RUN instruction will execute any commands in a new layer on top of the current image and commit the results. The resulting committed image will be used for the next step in the Dockerfile.
There are 2 forms:
Shell form:
RUN <command> (the command is run in a shell, which by default is /bin/sh -c on Linux or cmd /S /C on Windows)
Exec form:
RUN ["executable", "param1", "param2"]
The default shell for the shell form can be changed using the SHELL command.
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