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I built the jenkins service on a vm on an ubuntu system via docker run -. Now if I want to automate the image creation via jenkins & harbor configuration, I need to install docker in the jenkins container, which is used to execute the docker build command.
On my ubuntu host, I installed docker via snap install docker. which docker to see that docker is installed in /snap/bin/docker. So I used the following command while running docker run:
sudo docker run -d -p 80:8080 -p 50000:50000
-v /home/my/jenkins_home:/var/jenkins_home
-v /var/run/docker.sock:/var/run/docker.sock
-v /snap/bin/docker:/usr/bin/docker
-v /etc/docker/daemon.json:/etc/docker/daemon.json
jenkins/jenkins:lts
(Here I tried /usr/bin/docker:/usr/bin/docker and was prompted that /usr/bin/docker could not be found)
After following the above steps to create the jenkins container, I ran the docker command after entering the container via docker exec *** -it bash, only to find that the snap command was actually executed.
During my troubleshooting, I found a connection configuration on the ubuntu host via the ll /snap/bin/docker command:
$ ll /snap/bin/docker
lrwxrwxrwx 1 root root 13 Mar 27 08:51 /snap/bin/docker -> /usr/bin/snap*
Has anyone encountered this problem and is there any solution?
2
Answers
I see that you are trying to run the docker command inside the container.
The docker command should be executed on a host, not in containers.
Yes, millions of developers before you. There are several similar questions even on this site.
Yes, install docker inside the Jenkins container. Typically, you would create a Dockerfile that will build your Jenkins agent image.
Strongly do not mount executable files from host. Consider not sharing configuration files from /etc/ from host with docker containers. Consider re-reading introduction to Docker, why it is used, consider interesting yourself in best practices with Docker. If you want, research docker-in-docker.
Typically, there is jenkins controller that is only running the controller (and a minimal internal node) and jenkins-agents, and the agents have access to docker for workflows to run. Typically, agents are added the docker client, like docker not found inside jenkins pipeline or https://medium.com/@yassine.essadraoui_78000/jenkins-docker-in-docker-b7630c7b9364 or https://devopscube.com/docker-containers-as-build-slaves-jenkins/?unapproved=63874&moderation-hash=d5464a664348e998b876cdc761385caa#comment-63874 or https://rokpoto.com/jenkins-docker-in-docker-agent/ etc.