Jenkins (1) What is Jenkins: Complete Guide to DevOps Automation Introduction

What is Jenkins

Jenkins is an open-source automation server primarily used for implementing Continuous Integration (CI) and Continuous Delivery (CD). Simply put, it acts like a diligent assistant that can automatically execute various repetitive development tasks.

These tasks include building applications, running test cases, and deploying code to different environments. By automating these processes, Jenkins helps development teams reduce human errors, improve work efficiency, and enhance software quality.

For developers new to DevOps, Jenkins is an excellent tool for getting started with CI/CD concepts. It’s not only powerful but also has abundant learning resources and community support.

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Why Choose Jenkins

Among numerous CI/CD tools, Jenkins is widely popular for four key reasons:

Cost-Effective

Open Source and Free: Jenkins is an open-source project that anyone can use and modify for free. This is a very practical choice for teams with limited budgets or individual developers.

Excellent Scalability

Rich Plugin Ecosystem: Jenkins has over 1,500 official and community-developed plugins. Whatever tool or service you need to integrate, you can almost always find a corresponding plugin, greatly reducing the cost of custom development.

Abundant Learning Resources

Active Community Support: Jenkins has a large and active developer community providing extensive documentation, discussion forums, and technical support. When you encounter problems, you can usually find solutions quickly.

Strong Integration Capabilities

Seamless Integration with Mainstream Tools: Jenkins can easily integrate with Git, Docker, Kubernetes, AWS, and other modern development tools and cloud platforms. This high degree of compatibility allows it to adapt to various development environments.

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Core Concepts of Jenkins

To effectively use Jenkins, you must first understand its core concepts. The following four concepts are the foundation of Jenkins architecture:

Pipeline

Code-Defined Build Process: Jenkins Pipeline is a powerful plugin suite that allows you to define the entire CI/CD process with code. Like writing programs, you can define the complete workflow from code pulling, building, testing to deployment. This approach is called “Pipeline as Code.”

Node

Where Work Gets Executed: A Node is a physical or virtual machine where Jenkins executes work. There are mainly two types:

• Master Node: Jenkins control center responsible for scheduling and managing work
• Agent Node: Working machines that actually execute build tasks

Job

Basic Unit of Tasks: A Job is the basic unit in Jenkins that defines specific build tasks. Each Job can include multiple steps such as code pulling, compilation, and testing, and is the core component of Jenkins operation.

Executor

Key to Parallel Processing: An Executor is the execution unit that actually runs Jobs. A Node can be configured with multiple Executors, allowing multiple Jobs to run in parallel simultaneously, greatly improving build efficiency.

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Summary

Through this article, we’ve learned about Jenkins, this powerful automation tool. It’s not only a free open-source solution but also an indispensable core tool in modern DevOps practices.

Jenkins’ main value lies in:

• Automating Repetitive Tasks: Reducing human errors and improving development efficiency
• Rich Ecosystem: Over 1,500 plugins meeting various needs
• Flexible Architecture Design: Concepts like Pipeline, Node, Job, and Executor make the system both powerful and easy to scale

For developers looking to enter the DevOps field, Jenkins is an ideal starting point. In the upcoming series articles, we will explore in depth how to set up and configure Jenkins, enabling you to practically use this powerful tool.

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Jenkins Series Article Navigation

This is the first article in the Jenkins tutorial series. Subsequent articles will take you from zero to building a complete CI/CD environment:

1. Jenkins (1) What is Jenkins ← You are reading ✅
2. Jenkins (2) Complete Server Setup Guide - Quick Jenkins environment setup using Docker
3. Jenkins (3) Complete SSH Credentials Configuration Guide - Setting up secure code access

Recommended Related Technical Articles

• Getting Started with GitHub Container Registry - Container deployment and CI/CD integration
• Using SSH to Manage Multiple GitHub Accounts - Advanced Git account management techniques
• Design Patterns Series - Software architecture design best practices

We recommend reading the Jenkins series articles in sequence, as each one lays a solid foundation for the next step of implementation.

TIP

For more information about Jenkins, please refer to the Jenkins Official Documentation.