📘Cisco DevNet Associate (200-901 DEVASC)

1. Introduction

A CI/CD pipeline is an automated process used by development and operations teams to build, test, and deploy software or infrastructure changes.

CI/CD stands for:

CI – Continuous Integration
CD – Continuous Delivery / Continuous Deployment

In modern IT environments, infrastructure is often managed using Infrastructure as Code (IaC). This means configuration files, scripts, and templates define how networks, servers, and services should be deployed.

Instead of manually configuring devices or systems, engineers update code files. The CI/CD pipeline automatically tests and deploys those changes.

This approach is widely used in network automation, cloud infrastructure, and application deployment.

2. What is a CI/CD Pipeline?

A CI/CD pipeline is a sequence of automated steps that:

Takes code changes from developers
Builds the code or configuration
Tests the changes
Deploys them into an environment

The pipeline ensures that every change is verified before deployment, reducing human errors and improving reliability.

For infrastructure automation, the pipeline may deploy:

Network configurations
Infrastructure templates
Automation scripts
Containerized services
Cloud infrastructure resources

3. Continuous Integration (CI)

Definition

Continuous Integration (CI) is the practice of automatically integrating code changes into a shared repository and verifying them through automated builds and tests.

Whenever a developer updates the code, the CI system automatically:

Retrieves the new code
Builds the project
Runs automated tests
Reports results

Example in an IT Environment

A network engineer updates a Python automation script used to configure switches.

The CI system automatically:

Pulls the updated script
Runs syntax validation
Executes automated test cases
Verifies API calls or configuration templates

If tests fail, the change is rejected.

4. Continuous Delivery (CD)

Definition

Continuous Delivery means the system automatically prepares validated code for deployment.

After successful testing:

The code is packaged
Deployment artifacts are created
The system is ready to release the update

However, deployment may still require manual approval.

Example in Infrastructure Automation

After tests succeed:

The pipeline generates configuration templates
Infrastructure scripts are prepared
The update is ready to be deployed to production

An administrator may approve the final deployment.

5. Continuous Deployment

Definition

Continuous Deployment goes one step further than continuous delivery.

All validated changes are automatically deployed to production without manual approval.

Example

A pipeline automatically:

Validates a new network configuration template
Tests it in a simulated environment
Deploys it to production routers or switches

6. Components of a CI/CD Pipeline

A CI/CD pipeline contains several important components.

6.1 Source Code Repository

The source repository stores the code used for automation.

It includes:

Infrastructure templates
Python scripts
Configuration files
Test scripts
Documentation

A version control system tracks all changes.

Common tools include:

Git repositories
Code hosting platforms

Why it is important

It allows teams to:

Track code history
Collaborate on infrastructure automation
Revert to previous versions if necessary

6.2 Version Control System (VCS)

A version control system manages different versions of the code.

Key functions include:

Tracking changes
Managing branches
Allowing multiple engineers to work on the same project

Example in automation

A network automation repository may contain:

Python scripts for device configuration
YAML files for network policies
Infrastructure templates

If a new change causes issues, engineers can roll back to an earlier version.

6.3 Build Stage

The build stage prepares the automation code for testing.

For infrastructure automation, this stage may:

Install dependencies
Validate scripts
Package configuration templates
Compile software if needed

Example

A pipeline might:

Install required Python libraries
Package Ansible playbooks
Validate YAML configuration files

6.4 Automated Testing

Testing ensures that infrastructure automation works correctly.

Types of tests include:

Syntax Testing

Checks whether the code structure is correct.

Example:

Python syntax validation
YAML format validation

Unit Testing

Tests individual parts of the code.

Example:

Testing a function that generates router configurations.

Integration Testing

Ensures different components work together.

Example:

Testing API communication with network controllers
Verifying configuration deployment through automation scripts

Infrastructure Testing

Tests configuration changes in a test environment or simulation platform.

Example:

Testing network configuration in a virtual lab
Verifying that routing policies apply correctly

6.5 Artifact Repository

After the build and tests succeed, the pipeline stores artifacts.

Artifacts are packaged outputs such as:

Configuration templates
Container images
Software packages
Automation scripts

These artifacts are stored in a repository for deployment.

6.6 Deployment Stage

The deployment stage applies the automation to target environments.

Possible environments include:

Development environment
Testing environment
Staging environment
Production infrastructure

Deployment methods may include:

API calls
Configuration management tools
Infrastructure provisioning tools

Example

The pipeline deploys:

Network configuration to routers
Cloud infrastructure templates
Containerized applications

6.7 Monitoring and Feedback

After deployment, the system must monitor the results.

Monitoring includes:

System logs
Performance metrics
Error reports

If problems occur:

alerts are generated
pipelines may automatically roll back changes

7. CI/CD Pipeline Workflow

A typical CI/CD pipeline workflow looks like this:

Engineer updates automation code
Code is pushed to a repository
CI pipeline starts automatically
Code is built
Automated tests run
Artifacts are created
Deployment stage begins
Infrastructure changes are applied
Monitoring verifies deployment success

8. Benefits of CI/CD in Infrastructure Automation

CI/CD pipelines provide many advantages.

8.1 Faster Deployment

Automation allows infrastructure changes to be deployed quickly.

Instead of manual configuration:

scripts update devices
templates deploy infrastructure automatically

8.2 Reduced Human Errors

Manual configuration can introduce mistakes.

CI/CD pipelines ensure:

consistent configurations
validated deployments
automated testing

8.3 Improved Collaboration

Teams work on shared repositories.

Developers, network engineers, and operations teams can:

review code changes
track updates
collaborate efficiently

8.4 Continuous Testing

Every change is automatically tested.

This helps detect:

configuration errors
API failures
compatibility issues

before production deployment.

8.5 Faster Issue Detection

Because pipelines run automated tests frequently, problems are identified early.

This reduces downtime and improves reliability.

8.6 Consistent Infrastructure

CI/CD ensures infrastructure is deployed in a standardized way.

This leads to:

predictable configurations
consistent environments
easier troubleshooting

8.7 Better Security

Security checks can be included in the pipeline.

Examples:

secret detection
vulnerability scanning
configuration validation

9. Example CI/CD Pipeline in Network Automation

A network automation pipeline may perform the following tasks:

Engineer updates a Python script that configures network devices
Code is pushed to the repository
CI system runs automated tests
Configuration templates are generated
Virtual network lab tests the configuration
Approved configuration is deployed to production devices
Monitoring tools verify device status

This process ensures that network configuration changes are safe and consistent.

10. Common CI/CD Tools Used in Infrastructure Automation

Examples of commonly used tools include:

CI/CD Platforms

Jenkins
GitLab CI
GitHub Actions
Azure DevOps

Infrastructure Automation Tools

Ansible
Terraform
Puppet
Chef

Testing Tools

pytest
network simulation tools
infrastructure validation tools

11. CI/CD in DevOps and Network Automation

CI/CD pipelines are a key part of DevOps practices.

They enable:

automated infrastructure management
continuous testing
faster software delivery

For network automation, CI/CD helps manage:

configuration updates
infrastructure provisioning
API-based device management

12. Key Points for the DEVASC Exam

You should remember the following:

CI/CD Pipeline

Automated workflow that builds, tests, and deploys code or infrastructure changes.

Continuous Integration (CI)

Integrates code changes frequently
Runs automated builds and tests

Continuous Delivery

Prepares code for deployment
Deployment may require approval

Continuous Deployment

Automatically deploys changes to production

Main Components of a CI/CD Pipeline

Source code repository
Version control system
Build stage
Automated testing
Artifact repository
Deployment stage
Monitoring and feedback

Key Benefits

Faster infrastructure deployment
Reduced configuration errors
Improved collaboration
Continuous testing
Consistent infrastructure management