Starting With Jenkins
As we all know Jenkins is one of the most demanded tool in world of DevOps. Companies who are using Jenkins is increasing day by day. So here I am going to start a small tour of Jenkins which will lead towards some knowledge in Jenkins and DevOps technology. In this process my friend Kesha Shah also going to help me and we are working as a team! Hope this will give you some good knowledge in Jenkins world so lets start…
What is Jenkins and why we need it?
Basically Jenkins is a Continuous Integration and Continuous Delivery tool. It is used for making our workflow fully automatic. Using this we can integrate multiple tools and makes it more easier.
Jenkins is light weight tool all the functionality of Jenkins comes through the plugins. If you don’t know much about plugin then you can think it (Jenkins) as a empty box. Now we install plugin for some specific tools, so using this plugin Jenkins learn all the commands respective to that tool.
Lets understand this with GitHub Plugin.
When Jenkins downloaded it don’t know anything about git or GitHub. But when we install a plugin for this it will download all the GitHub related commands code and all. Now you have to only tell download this code from this account. Jenkins automatically use git clone command and download the code from GitHub but here we don’t need to mention somewhere use this command use this way, Jenkins automatically going to run the command behind the seen for you. This facility comes in Jenkins through Plugins.
For understanding Jenkins workflow better, lets assume one situation.
You are working in good company and developer is keep on releasing update to your app and as we all know we have to perform lots of operation on the raw source code. Like we have to create a image and build/compile it, then deploy it in our testing environment, if its works find deploy it to the production environment again do some unit testing or some other kind of testing. And finally our product is ready. If you think on first side, then it will be quite easy to do it manually but assume you have to do it everyday. So now is it feasible? Definitely not, we have to found some automate way to do this thing. Here the role of Jenkins come into the picture. So first of all let me show you how to install Jenkins in you system.
If you think above situation it is like a infinite cycle. Once you finish entire process in some time developer again change something in the code and you have to repeat all the steps.
So before going for some Hands-on, lets check some basic terminology and some useful details of Jenkins.
In Jenkins we are mostly going to use term Job. Here we are Just assigning something which is known as Job. Sometimes job also known as Item. So item and Job both are same thing.
Like download code from GitHub. Lets create a job for it and when you run this job it will download the code and store it in their database. Running a Job is known as Building a Job in Jenkins, so for running a job you have to click on Build Now.
Jenkins by default works on port 8080. It follows master slave architecture but in simple case where we have only one OS master is also working as a slave.
For connecting to Jenkins we have 3 different.
- WebUI
- CLI
- Pipeline as code
Well don’t worry and pressurized your mind thinking on what all this stuff. Once you see some hands on part you will definitely going to love Jenkins.
So hope you like this we are going to cover installation part in next blog.
