GitLab CI/CD [WikiElosys]

This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong.
====== GitLab CI/CD ======


===== What is the difference between Continuous Integration, Continuous Delivery, and Continuous Deployment? =====

===== Continuous Integration (CI) =====

 CI involves developers merging their changes into a shared repository several times a day. Each merge is then automatically built and tested to catch 
 bugs early in the development cycle.

 Key Features:
  - Frequent code check-ins
  - Automated building and testing
  - Quick detection of integration issues




===== Continuous Delivery (CD) =====

CD is an extension of Continuous Integration. It ensures that the codebase is always in a deployable state. This practice allows you to manually trigger deployments to production (or other environments), but everything up to that point is automated.

Key Features:
  - Codebase is always deployable
  - Manual approval is required for deployment to production
  - Includes automated testing and staging

===== Continuous Deployment (also CD): =====
This is an advanced stage of CD. Here, every change that passes the automated testing phase is automatically deployed to the production environment without manual intervention.

Key Features:
  - Fully automated pipeline, including production deployment
  - No manual intervention for deployments
  - Quick release of new features and fixes
{{ :discussion:elosys:gitlab_ci:cicd.png?600 |}}

====== What is gitlab ci :======

A CI/CD pipeline is an automated process utilized by software development teams to streamline the creation, testing and deployment of applications. "CI" represents continuous integration, where developers frequently merge code changes into a central repository, allowing early detection of issues.

====== What is the difference between GitLab and GitLab Runner? ======

from docs GitLab Runner is an application that works with GitLab CI/CD to run jobs in a pipeline. you should install GitLab Runner on a machine that's separate from the one that hosts the GitLab instance for security and performance reasons.

====== What is a GitLab Runner? ======
A GitLab Runner is an executer used to run CI/CD jobs and send the results back to GitLab. Runners are the workhorses of GitLab CI/CD pipelines, performing tasks such as building, testing, and deploying code. They are flexible and can run jobs in different environments, such as Docker, shell, and Kubernetes.



====== Why Use GitLab Runners? ======
GitLab Runners provide the following benefits:

  - Scalability: Easily scale the number of runners to handle multiple jobs concurrently.
  - Flexibility: Configure runners to use different execution environments tailored to specific job requirements.
  - Isolation: Run jobs in isolated environments to ensure consistency and prevent conflicts.

====== Git Lab Architecture ======

The GitLab architecture begins by choosing the instance type, whether it’s self-managed or hosted on gitlab.com. Following this, you’ll proceed to register the runners, which are available in three categories: shared runners, specific runners, and group runners. These runners play a crucial role in fetching jobs from the instance and routing them to executors. These executors, residing on the same server or instance as the runner, can be configured to utilize various methods such as Docker or shell scripts to execute tasks. After completing the job, the executor transmits the results back to the runner, which then relays them to either the GitLab instance or the self-managed environment. Tags are employed within scripts to precisely define which runners should be utilized for specific tasks.
{{ :discussion:elosys:gitlab_ci:gitlab_architecture.png?600 |}}{{:discussion:elosys:gitlab_ci:1722236910034.gif?400|}}

====== Types of GitLab Runners ======

===== 1. Shared Runners =====
Shared Runners are available to all projects within a GitLab instance. They are managed by the GitLab administrator and are ideal for general-purpose tasks and smaller projects. Shared runners are convenient as they do not require individual setup for each project.

===== 2. Dedicated Runners =====
Dedicated Runners (or specific runners) are assigned to specific projects or groups. They provide greater control and customization for the project’s requirements. Dedicated runners are particularly useful for:

Projects with specific build environments.
Handling sensitive or resource-intensive tasks.
Ensuring dedicated resources are available for critical pipelines.

=====  Gitlab Runner Installation Steps =====
====Step 1: Adding Repositories with Bash Script =====
Download and run an automatic bash script that adds the necessary repositories to prepare for installing GitLab Runner on the system.

==== Step 2: Installing GitLab Runner ====

You can install GitLab Runner on your system by following the official documentation: [GitLab Runner Installation Guide](https://docs.gitlab.com/runner/install/).

==== Step 3: Registering GitLab Runner ====

1. '''Log in to GitLab'''  

2. '''Access Project Settings'''  
   - Go to your project in GitLab.  
   - In the left sidebar, select '''Settings''' > '''CI/CD'''.

3. '''Find the Registration Token'''  
   - Scroll to the '''Runners''' section.  
   - Under '''Project Runners''', locate the '''Registration Token''' and copy it.

4. '''Register the Runner on the Server'''  
   - On the server where you wish to register the runner, execute the following command:
   
        sudo gitlab-runner register
    
5. '''Enter Runner Details'''  
   - When prompted, provide:
     - '''GitLab instance URL''': https://git.elosys.net
     - '''Registration Token''': Paste the token copied from your project’s settings.
     - '''Description''': Enter a descriptive name, such as elosys-project-runner.
     - '''Tags''': Specify any tags for the runner (optional).
     - '''Executor Type''': Choose the executor (e.g., docker, shell).

6. '''Confirm Registration'''  
   - Return to '''Settings''' > '''CI/CD''' > '''Runners''' in your GitLab project.  
   - Verify that the runner is listed under '''Project Runners''' and is active.
   - 
=== GitLab Runner Docker Executor Configuration ===

== File Location ==
To edit the configuration file, open it with nano:

  sudo nano ~/.gitlab-runner/config.toml
  
 Configuration Details   Below is the configuration for the [[runners.docker]] section:

    [runners.docker]
    tls_verify = false
    image = "docker:stable"
    dns = ["8.8.8.8"]
    extra_hosts = ["register.elosys.net:195.154.29.195"]
    privileged = false
    disable_entrypoint_overwrite = false
    oom_kill_disable = false
    disable_cache = false
    volumes = ["/var/run/docker.sock:/var/run/docker.sock", "/cache"]
    shm_size = 0
    network_mode = "host"
elosys/gitlab_ci-cd.txt
Last modified: 2024/11/10 19:37
by mohamed_adda