Top Jenkins Interview Questions And Answers
Top Answers to Jenkins Interview Questions
First let us compare Jenkins with TeamCity:
|Popularity||Widely used||Not so widely used|
The software prerequisites for installing Jenkins is that first you need to install Java Development Kit. It also needs you to install the Jakarta Enterprise Edition. Jenkins also comes with an embedded Jetty runtime that can be used if WebSphere or Tomcat is not available.
These are some of the steps used for working with a third-party tool in Jenkins.
- You have to first install the third-party software
- You need to have the plug-in that supports the third-party tool.
- You have to configure the third-party tool in the admin console.
- You can then use the plug-in from the Jenkins build job.
These are the mechanisms for starting a Jenkins node agent:
- From the browser window launch a Jenkins node agent.
- From the command line launch a Jenkins node agent.
When you launch a Jenkins node agent it will download a JNLP file. A new process is launched on the client machine by the JNLP when it runs.
Within the XML configuration each Jenkins build is stored. When this folder is copied, the configuration of all the build jobs that are managed by the Jenkins master are backed up. If you can perform a Jenkins Git integration, then it is good. When you copy the contents of the folder, you will see that the build jobs described in the folder will be restored when the Jenkins server is started the next time.
A complete Jenkins pipeline will include building a project from the source code, putting it through a variety of unit, integrating, testing for user acceptance and performance and then finally deploying the packaged application on an application server.
So the steps in a Jenkins pipeline will include:
There is a folder that contains a file named config.xml. you need to change the settings to false for the security to be disabled when Jenkins is started the next time.
Jenkins can be thought of as an open source automation tool that is used for continuous integration. You will be able to continuously test your software projects so that the developers will be able to integrate the changes to the project. You can also integrate with a large number of testing and deployment technologies.
Here are some of the most important advantages of Jenkins:
- You will get an automated build report every time a change is made to the source code
- You will be able to achieve continuous integration with agile methodology principles
- You can automate the maven release project with a few simple steps
- The bugs can be easily tracked at the early development stage.
Here we list some of the requirements for using Jenkins:
- A source code repository like a Git repository
- A build script like a Maven script that is checked into the repository.
Here we are listing some of the important plugins that are used with Jenkins:
- Git repository
- Amazon EC2
- HTML Publisher
- JDK parameter plugin
- Configuration slicing plugin.
First you need to create the Jenkins job by going to the Jenkins top page, selecting a “New Job” and building a freestyle software project.
Some of the elements of a free style project include:
- You need a CVS or a subversion where your source code will reside
- When the Jenkins will perform the builds, you will need the optional triggers
- You need a build script like a Maven or Ant where actually the script is built
If you want to create a backup for your file then you need to regularly backup your Jenkins_Home directory. This will include all the build jobs configuration, all the slave node configuration and the build history. If you want to create a Jenkins backup, you can copy a job directory to the clone or can rename the directory.
Here we will explain the process for securing Jenkins. First you need to ensure global security. Then you have to make sure that the Jenkins is integrated with the user directory through appropriate plugin. The project matrix is enabled for fine tuning the access. Using the custom version-controlled script for automating the process of rights and privileges in Jenkins. The access to Jenkins data or folder is limited. You will run security audits on it.
Initially Jenkins was called as Hudson and there were some issues and due to this the name was changed to Jenkins from Hudson.
First you need to open the console output where the broken build is created and then see if there are any file changes that were missed. If you do not find any issues in this manner, then you can update your local workspace and replicate the problem and then try to solve it.
First you need to copy your jobs directory from the old to the new server. There are multiple ways to do it. You can either move the job from installation to simply copying the corresponding job directory, or you can make a clone of the job directory by making an existing job copy. First you need to have a different name which you can rename later.
Here there are some steps for scheduling of builds in Jenkins
- First you should have a source code management commit
- You have to complete the other builds
- You have to schedule it to run at a specified time
- Give a manual build request.
Some of the important SCM tools that are supported by Jenkins include: