Dockerfile is basically a text file. It contains some set of instructions. Automation of docker image creation.

Docker Components =>

FROM: for a base image the command must be on top of the docker

RUN: To execute Command, it will create a layer in the image.

MAINTAINER: Author/owner/description

COPY: Copy files from the local system (docker VM) we need to provide a source, destination(We cant download file from the internet and any remote directory)

ADD: Similar to copy but, it provides a feature to download files from the internet, also we extract files at the docker image side.

EXPOSE: To Expose ports such as port 8080 for tomcat, port 80 for Nginx, etc.

WORKDIR: To set a working directory for a container.

CMD: Execute commands but during container creation

ENTRYPOINT: Similar to CMD, but has higher priority over CMD, first commands will be executed by ENTRYPOINT only.

#devops #docker #dockerfiles #containerization