Reasons:
- Using ephemeral Docker containers as Jenkins build slaves for various stages result in better resource utilization.
- Spinning up a new container takes less than a minute, every build spins up a new container, builds the project, and is destroyed. This way, you can reduce the number of static Jenkins build VMs.
Full Answer
How to install Jenkins in a docker container?
STEP 2: PULL AND RUN THE CLOUDBEES JENKINS CONTAINER
- Stay in your Docker terminal window.
- Pull Jenkins from the public repo by running: docker pull jenkins/jenkins docker run -p 8080: 8080 --name=jenkins-master jenkins/jenkins
- Note that the “Jenkins initial setup” message in your shell window will generate a password for you. ...
- Open your favorite browser and point it to http://localhost:8080
How to run a docker image in Jenkins?
Setup
- Docker Environment. Follow the installation steps on the docker website. ...
- Multiple Docker Hosts. If you want to use more than just one physical node to run containers, you can use Docker Swarm Standalone or you can define more than one ...
- Jenkins Configuration. Docker plugin is a "Cloud" implementation. ...
- Creating a docker image. ...
What does Docker do, and when should you use it?
The docker run command allows you to run containers based on images. It is like running a virtual machine with a specific OS, only with containers. Here, instead of selecting the OS, you select the image. You can simply run docker run followed by the image name, but this will create a container with no name and only an ugly ID.
How to build and deploy in Docker?
- Launch an instance with the Amazon Linux 2 or Amazon Linux AMI. ...
- Connect to your instance. ...
- Update the installed packages and package cache on your instance. ...
- Install the most recent Docker Engine package. ...
- Start the Docker service. ...
- Add the ec2-user to the docker group so you can execute Docker commands without using sudo . ...
See more
Why Docker is needed for Jenkins?
Docker is a container engine that can create and manage containers, whereas Jenkins is a CI engine that can run build/test on your app. Docker is used to build and run multiple portable environments of your software stack. Jenkins is an automated software testing tool for your app.
Do you need Docker to run Jenkins?
Prerequisites. If you want to try out the sample configurations, you'll need a system with Docker and Docker Compose installed. You'll also need access to Docker Hub to download the latest Jenkins images.
Why do we require Docker?
Docker is an open source containerization platform. It enables developers to package applications into containers—standardized executable components combining application source code with the operating system (OS) libraries and dependencies required to run that code in any environment.
Is Docker necessary for DevOps?
The Docker tool was designed for developers and system administrators, an essential part of DevOps. With Docker, developers can focus on application development rather than being worried about the platform where it will run. They can start all by themselves using ready-to-use Docker programs.
How do Jenkins and Docker work together?
Jenkins builds a new docker image and pushes it to the Docker registry. Jenkins notifies Kubernetes of the new image available for deployment. Kubernetes pulls the new docker image from the docker registry. Kubernetes deploys and manages the docker instance/container.
Which is better Jenkins or Docker?
Docker Swarm is more comprehensive and highly customizable, whereas Jenkins is customizable with the help of plugins. Kubernetes and Jenkins provide low fault tolerance unlike Docker. Docker is a container engine that can make and handle containers, whereas Jenkins is a CI/CD model that can build and test applications.
What is Docker used for in DevOps?
Containers simplify the build/test/deploy pipelines in DevOps. With Docker containers, developers own what's within the container (application and service, and dependencies to frameworks and components) and how the containers and services behave together as an application composed by a collection of services.
Why do developers use Docker?
Docker helps to ensure that all the developers have access to all the necessary bits and pieces of the software they work on. So if someone adds software dependencies, everyone has them when needed. If it is just one developer, there is no such need.
Why is Docker better than VM?
Advantages of Docker Containers Docker containers are process-isolated and don't require a hardware hypervisor. This means Docker containers are much smaller and require far fewer resources than a VM. Docker is fast. Very fast.
What is Jenkins Docker?
Docker is a platform for running applications in an isolated environment called a "container" (or Docker container). Applications like Jenkins can be downloaded as read-only "images" (or Docker images), each of which is run in Docker as a container.
What is difference between DevOps and Docker?
Docker allows the developer to build and run the software in a simple manner. DevOps teams can streamline containers in a cluster with the help of Kubernetes. It can even help them to effectively monitor the containers.
What is difference between Docker and Kubernetes?
While Docker is a container runtime, Kubernetes is a platform for running and managing containers from many container runtimes. Kubernetes supports numerous container runtimes including Docker, containerd, CRI-O, and any implementation of the Kubernetes CRI (Container Runtime Interface).
How do I run a Jenkins container?
To run Jenkins on a different port, swap out the first 8080 to your desired port:
How do I start Jenkins?
Download and run JenkinsDownload Jenkins Generic Java package (.war)Open up a terminal in the download directory.Run java -jar jenkins.war --httpPort=8080.Follow the instructions to complete the installation.
How does Jenkins work?
How Jenkins works. Jenkins runs as a server on a variety of platforms including Windows, MacOS, Unix variants and especially, Linux. It requires a Java 8 VM and above and can be run on the Oracle JRE or OpenJDK. Usually, Jenkins runs as a Java servlet within a Jetty application server.
How do I manually start Jenkins?
To restart Jenkins manually, you can use either of the following commands (by entering their URL in a browser).jenkins_url/safeRestart - Allows all running jobs to complete. ... jenkins_url/restart - Forces a restart without waiting for builds to complete.
Why is Jenkins deployment faster?
Faster deployment makes for easier management. For Jenkins usage, it's faster and easier to deploy/install in the docker way. Maybe you don't need the scale more easily feature right now. And since the docker is quite lightweight, so you can run more workloads.
Does Jenkins require Docker?
You list mainly the advantages of having "Jenkins as Code". Which is a very powerfull setup indeed, but does not necessary requires Docker.
Where should Docker be installed?
Docker should be installed on the server where you need to run a container and the user should be added to the docker group
Can Jenkins run Docker?
In this blog, we will integrate Jenkins with Docker so that we can have an automation to run the docker container directly from the Jenkins. We will create a freestyle and the pipeline job to run a docker image inside a container through Jenkins
What is Jenkins main machine?
Our main machine is a host for Jenkins container. When Jenkins needs to run tasks, it builds a docker container and runs specific commands on it. So we run dockers for jobs on our docker with Jenkins. If you try to run a virtual machine on a virtual machine, you can encounter many issues.
Can you run a Docker daemon with a specific user?
In most cases, we run docker daemon with a specific user, and all other users do not have access to it.
Can Jenkins run in Docker?
That would be all. With this configuration, we can run Jenkins in docker and use docker for builds. You can find Dockerfile and docker-compose.yml for presented example in here https://github.com/smoogie/jenkins_docker_example
Can Docker run on a virtual machine?
If you try to run a virtual machine on a virtual machine, you can encounter many issues. But there is the way to run all dockers outside our container, directly on the host. In that case, all docker commands dispatched inside the container will be processed on the host machine.
Can Jenkins run Docker containers?
Now we build a docker image again and run the container ( docker-compose build, docker-compose up ). From now on, our Jenkins can run docker’s containers on the host without any issues.
What is the difference between Docker and Jenkins?
What are the differences between Docker and Jenkins? 1 Docker is a container engine that can create and manage containers, whereas Jenkins is a CI engine that can run build/test on your app. 2 Docker is used to build and run multiple portable environments of your software stack. Jenkins is an automated software testing tool for your app. Also, don't forget that Jenkins started as a build tool for Java apps. 3 Jenkins provides an easy interface to create and manage multiple CI/CD pipelines using its plugins. Sometimes people build Docker images and run Docker containers using Jenkins CI/CD pipeline for software testing purposes. 4 You can easily trigger in-server/in-container deployments based on Chef, Ansible, and Salt using Jenkins CI/CD pipeline.
What is Jenkins CI/CD?
Also, don't forget that Jenkins started as a build tool for Java apps. Jenkins provides an easy interface to create and manage multiple CI/CD pipelines using its plugins. Sometimes people build Docker images and run Docker containers using Jenkins CI/CD pipeline for software testing purposes.
