Kubernetes Networking with Calico and ContainerLab

🎯 Learn Kubernetes networking hands-on! This repository provides a complete toolkit for deploying and experimenting with Calico CNI, ContainerLab topologies, and Kubernetes networking concepts

Perfect for:

🔬 Network engineers exploring Kubernetes networking
📚 Students learning CNI implementations and BGP routing
🛠️ DevOps practitioners understanding pod-to-pod communication
🌐 Security professionals studying network policies and micro-segmentation

Prerequisites

AWS CLI configured with appropriate permissions
Terraform (1.0+)
Ansible (2.9+)
SSH key pair in ~/.ssh/id_rsa (public key in ~/.ssh/id_rsa.pub)

Getting Started

🎬 Video Walkthrough

Deploying the Lab Environment

Clone this repository:

git clone https://github.com/aadhilam/k8-networking-calico-containerlab.git
cd k8-networking-calico-containerlab

Download and place the Arista cEOS image:
- Follow the Downloading the Arista cEOS Image instructions above
- Place the downloaded cEOS64-lab-4.34.0F.tar.xz file in the containerlab/ directory:
```
cp ~/Downloads/cEOS64-lab-4.34.0F.tar.xz containerlab/
```
Run the deployment script:
```
chmod +x deploy.sh
./deploy.sh
```

The deployment script will:

Provision a t3.2xlarge EC2 instance in us-east-1 using Terraform
Configure the instance with Docker, ContainerLab, Kind, and kubectl using Ansible
Copy lab files to the instance
Establish an SSH session to the instance

Working with the Lab

Once connected to the EC2 instance:

ContainerLab is available for creating network topologies
Kind is available for creating Kubernetes clusters
Docker is configured and ready to use
The ubuntu user has passwordless sudo access

Lessons

Infrastructure Details

Instance Type: t3.2xlarge (8 vCPUs, 32GB RAM)
Storage: 50GB GP3 SSD volume
Operating System: Ubuntu 22.04 LTS
Pre-installed Tools:
- Docker
- ContainerLab
- Kind (Kubernetes in Docker)
- kubectl
- jq, curl, tcpdump, bridge-utils, iproute2

Project Structure

container-labs/
├── ansible/
│   └── playbook.yml        # Ansible configuration for the instance
├── containerlab/           # ContainerLab topologies and configurations
├── images/                 # Documentation images
├── deploy.sh               # Main deployment script
├── destroy.sh              # Cleanup script
├── main.tf                 # Terraform infrastructure definition
├── variables.tf            # Terraform variable definitions
└── outputs.tf              # Terraform output definitions

Cleanup

When you're done with the lab environment, you can clean everything up:

chmod +x deploy.sh
./destroy.sh

This script will:

Destroy all Terraform-managed resources (EC2 instance)
Remove local temporary files

Notes

The EC2 instance public IP is saved to ec2_ip.txt for easy reference
The ubuntu user is configured with passwordless sudo and Docker group membership
Docker environment variables and completions are automatically loaded in the shell

Connection Requirements:

Your SSH private key should be in ~/.ssh/id_rsa
The security group allows SSH access (port 22) from your IP
The instance will have a public IP address for direct access

Troubleshooting Connection Issues:

# If you get permission denied, ensure your key has correct permissions
chmod 600 ~/.ssh/id_rsa

# Test connection with verbose output
ssh -v ubuntu@$(cat ec2_ip.txt)

# Connect using specific key file
ssh -i ~/.ssh/id_rsa ubuntu@$(cat ec2_ip.txt)

Downloading the Arista cEOS Image

Several labs in this repository (06-calico-overlay, 07-calico-bgp, 08-calico-bgp-lb, 09-multi-ippool, 10-calico-bgp-ippool) use an Arista cEOS (containerized EOS) switch image. You'll need to download this image before running those labs.

Steps to Download

Create an Arista Account (free):
- Go to https://www.arista.com/en/user-registration
- Complete the registration form and verify your email
Download the cEOS Image:
- Log in to your Arista account at https://www.arista.com/en/login
- Navigate to Software Downloads → cEOS-lab
- Or go directly to: https://www.arista.com/en/support/software-download
- Select cEOS-lab from the product list
- Download cEOS64-lab-4.34.0F.tar.xz (or the latest available version)
Place the Image in the ContainerLab Directory:
- Copy the downloaded image to /containerlab/ directory:
```
cp ~/Downloads/cEOS64-lab-4.34.0F.tar.xz containerlab/
```
Image Import (automatic):
- The deploy.sh scripts in the relevant labs will automatically import the image into Docker:
```
docker import containerlab/cEOS64-lab-4.34.0F.tar.xz ceos:4.34.0F
```

Note: The cEOS image is proprietary and cannot be distributed with this repository. You must download it directly from Arista with your own account.