Day2: 3.Write example docker file with 2 CMD, 2 ENTRYPOINT and 1 CMD/1ENTRYPOINT and write down a behaviour of it
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docker file with 2 CMD, 2 ENTRYPOINT
dockerfile6
FROM ubuntu
MAINTAINER Anoop << anoop@abc.com>>
ENV DEBIAN_FRONTEND=noninteractive
RUN apt-get update
RUN apt-get -y install tzdata
RUN apt-get install git -y && apt-get install -yq apache2
CMD echo "CMD_Hello_world_1"
CMD echo "CMD_Hello_world_2"
ENTRYPOINT ["/bin/echo", "ENTRY_Hello_1"]
ENTRYPOINT ["/bin/echo", "ENTRY_Hello_2"]
root@ip-172-31-28-155:/tmp/anoop# docker build -f dockerfile6 -t anoop_docker6_1 .
Sending build context to Docker daemon 7.168kB
Step 1/10 : FROM ubuntu
---> fb52e22af1b0
Step 2/10 : MAINTAINER Anoop << anoop@abc.com>>
---> Using cache
---> d127f9a0f32d
Step 3/10 : ENV DEBIAN_FRONTEND=noninteractive
---> Using cache
---> 6294578b4c0d
Step 4/10 : RUN apt-get update
---> Using cache
---> 0a42707c1dd0
Step 5/10 : RUN apt-get -y install tzdata
---> Using cache
---> c4305bb2f6f2
Step 6/10 : RUN apt-get install git -y && apt-get install -yq apache2
---> Using cache
---> 11c892976ccb
Step 7/10 : CMD echo "CMD_Hello_world_1"
---> Using cache
---> 0d97d714e8ee
Step 8/10 : CMD echo "CMD_Hello_world_2"
---> Using cache
---> 99b6c1dd58fe
Step 9/10 : ENTRYPOINT ["/bin/echo", "ENTRY_Hello_1"]
---> Using cache
---> 7319f0f64bd9
Step 10/10 : ENTRYPOINT ["/bin/echo", "ENTRY_Hello_2"]
---> Using cache
---> aebe16585944
Successfully built aebe16585944
Successfully tagged anoop_docker6_1:latest - Eventhough how many ENTRYPOINT and CMD, only last one in the docker file is considered
root@ip-172-31-28-155:/tmp/anoop# docker run -itd --name anoop_docker6_container anoop_docker6_1
7a041c9fd3300e59413af15b60bea77d882a26fd3ad68443b07aadbd11f78566
root@ip-172-31-28-155:/tmp/anoop# docker ps -a | grep anoop_docker6
7a041c9fd330 anoop_docker6_1 "/bin/echo ENTRY_Hel…" 59 seconds ago Exited (0) 58 seconds ago anoop_docker6_container
root@ip-172-31-28-155:/tmp/anoop# docker logs 7a041c9fd330
ENTRY_Hello_2 /bin/sh -c echo "CMD_Hello_world_2" - Tried to change pid1 --> CMD in docker layer is replaced with given command as part of "docker run"
root@ip-172-31-28-155:/tmp/anoop# docker run --name anoop_docker6_container_1 anoop_docker6_1 git --version
ENTRY_Hello_2 git --version
root@ip-172-31-28-155:/tmp/anoop# docker ps -a | grep anoop_docker6
dc5cbfae4db3 anoop_docker6_1 "/bin/echo ENTRY_Hel…" 6 seconds ago Exited (0) 5 seconds ago anoop_docker6_container_1
7a041c9fd330 anoop_docker6_1 "/bin/echo ENTRY_Hel…" 2 minutes ago Exited (0) 2 minutes ago anoop_docker6_container
docker file with 1 CMD, 1 ENTRYPOINT
dockerfile5
FROM ubuntu
MAINTAINER Rajesh Kumar << rajesh@scmgalaxy.com>>
ENV DEBIAN_FRONTEND=noninteractive
RUN apt-get update
RUN apt-get -y install tzdata
RUN apt-get install git -y && apt-get install -yq apache2
CMD echo "Hello world"
ENTRYPOINT ["/bin/echo", "Hello"] root@ip-172-31-28-155:/tmp/anoop# docker build -f dockerfile5 -t anoop_docker5 .
Sending build context to Docker daemon 6.144kB
Step 1/8 : FROM ubuntu
---> fb52e22af1b0
Step 2/8 : MAINTAINER Rajesh Kumar << rajesh@scmgalaxy.com>>
---> Using cache
---> 01477b86dfc8
Step 3/8 : ENV DEBIAN_FRONTEND=noninteractive
---> Using cache
---> 57a1ad7c1cea
Step 4/8 : RUN apt-get update
---> Using cache
---> 1207d5f945f3
Step 5/8 : RUN apt-get -y install tzdata
---> Using cache
---> e99c418f5399
Step 6/8 : RUN apt-get install git -y && apt-get install -yq apache2
---> Using cache
---> a10251de0aa1
Step 7/8 : CMD echo "Hello world"
---> Using cache
---> da7318408c65
Step 8/8 : ENTRYPOINT ["/bin/echo", "Hello"]
---> Using cache
---> 95fd2176a9d8
Successfully built 95fd2176a9d8
Successfully tagged anoop_docker5:latest - Entry point in the last statement of docker layer is worked first and CMD instrcution is considered as argument
root@ip-172-31-28-155:/tmp/anoop# docker images | grep anoop_docker5
anoop_docker5 latest 95fd2176a9d8 About an hour ago 259MB
root@ip-172-31-28-155:/tmp/anoop# docker run -itd --name anoop_docker5_container anoop_docker5
e48bf86c3251636b15cab89dae573ad8fae8e9ac5f36f61b9f5eaf0dede82f44
root@ip-172-31-28-155:/tmp/anoop# docker ps | grep anoop_docker5_container
root@ip-172-31-28-155:/tmp/anoop# docker ps -a | grep anoop_docker5_container
e48bf86c3251 anoop_docker5 "/bin/echo Hello /bi…" 17 seconds ago Exited (0) 16 seconds ago anoop_docker5_container
root@ip-172-31-28-155:/tmp/anoop# docker logs e48bf86c3251
Hello /bin/sh -c echo "Hello world"
root@ip-172-31-28-155:/tmp/anoop#
root@ip-172-31-28-155:/tmp/anoop# docker run --name anoop_docker5_container_1 anoop_docker5
Hello /bin/sh -c echo "Hello world"
root@ip-172-31-28-155:/tmp/anoop# docker ps -a | grep anoop_docker5_container
cd4e95c49666 anoop_docker5 "/bin/echo Hello /bi…" 4 seconds ago Exited (0) 3 seconds ago anoop_docker5_container_1
e48bf86c3251 anoop_docker5 "/bin/echo Hello /bi…" 3 minutes ago Exited (0) 3 minutes ago anoop_docker5_container - Tried to change pid1 --> CMD in docker layer is replaced with given command as part of "docker run"
root@ip-172-31-28-155:/tmp/anoop# docker run --name anoop_docker5_container_2 anoop_docker5 git --version
Hello git --version
root@ip-172-31-28-155:/tmp/anoop# docker ps -a | grep anoop_docker5_container
d9ffb519588d anoop_docker5 "/bin/echo Hello git…" 48 seconds ago Exited (0) 47 seconds ago anoop_docker5_container_2
cd4e95c49666 anoop_docker5 "/bin/echo Hello /bi…" About a minute ago Exited (0) About a minute ago anoop_docker5_container_1
e48bf86c3251 anoop_docker5 "/bin/echo Hello /bi…" 5 minutes ago Exited (0) 5 minutes ago anoop_docker5_container