Docker Command Part-13 By Raj Gupta

When ever we want a command will run after every time container will start then use ENTRYPOINT

[root@ip-172-31-82-31 dockerfiles]# vi Dockerfile
[root@ip-172-31-82-31 dockerfiles]# cat Dockerfile
FROM ubuntu:16.04
ENV NAME raj
ENV PASS password123
RUN mkdir -p /var/run/sshd
RUN apt-get update
RUN apt-get install -y python tree
ENTRYPOINT [ "tree" ]
[root@ip-172-31-82-31 dockerfiles]#

[root@ip-172-31-82-31 dockerfiles]# docker image build -t rajubuntu:85 .

[root@ip-172-31-82-31 dockerfiles]# docker container run -P -itd rajubuntu:85

when you want output of particular command like tree its version only every time

[root@ip-172-31-82-31 dockerfiles]# cat Dockerfile

FROM ubuntu:16.04

ENV NAME raj

ENV PASS password123

RUN mkdir -p /var/run/sshd

RUN apt-get update

RUN apt-get install -y python tree

ENTRYPOINT [ "tree" ]

CMD ["--version"]

[root@ip-172-31-82-31 dockerfiles]# docker image build -t rajubuntu:90 .

[root@ip-172-31-82-31 dockerfiles]# docker container run -P -it rajubuntu:90

tree v1.7.0 (c) 1996 - 2014 by Steve Baker, Thomas Moore, Francesc Rocher, Florian Sesser, Kyosuke Tokoro

[root@ip-172-31-82-31 dockerfiles]#