VPC creation on Linux

Chisolum Odoabuchi — Wed, 12 Nov 2025 18:47:04 +0000

This project demonstrates how to simulate Virtual Private Clouds (VPCs) using Linux network namespaces, virtual Ethernet (veth) pairs, and bridges. Each VPC contains public and private subnets, with routing, NAT, and isolation configured to mimic cloud VPC behavior (similar to AWS VPC).

Features
Create multiple isolated VPCs with their own bridges and routing rules.

Add public and private subnets to each VPC automatically.

Configure NAT for outbound Internet access via the host’s interface.

Enable IP forwarding for cross-network communication.

Automate setup and teardown using a Makefile for testing.

Easily extend to simulate VPC peering and routing policies.

Project Structure
├── Makefile
├── vpcctl.py
├── README.md
├── cleanup.sh
├── policies.json

Prerequisites
Make sure the following are installed on your Linux host:

Python 3.8 or higher

iproute2 utilities (ip, ip netns, etc.)

iptables

bridge-utils

make

sudo privileges

Usage
You can either run commands directly with vpcctl.py or automate everything using the Makefile. Option 1: Using the Makefile To create and test everything automatically:

This will:

Create two VPCs (vpc1 and vpc2) with their bridges.

Add public and private subnets to each.

Enable NAT for Internet-bound traffic.

Display the final namespace and route configurations.

To clean up everything:

make clean
Option 2: Using Python Script Directly You can also run individual operations with Python:

Create a new VPC
sudo python3 vpcctl.py create-vpc vpc1 --base-cidr 10.10.0.0/16
Add a public subnet
sudo python3 vpcctl.py add-subnet vpc1 public --type public --base-cidr 10.10.0.0/16
Add a private subnet
sudo python3 vpcctl.py add-subnet vpc1 private --type private --base-cidr 10.10.0.0/16
View network namespaces
ip netns list
Check routes inside a subnet
sudo ip netns exec vpc1-public ip route
Delete a VPC
sudo python3 vpcctl.py delete-vpc vpc1
Testing & Verification
After running make all, verify the following:

Namespace Check
ip netns list
You should see something like:

vpc1-public
vpc1-private
vpc2-public
vpc2-private
Routing Check
sudo ip netns exec vpc1-private ip route
You should see:

default via 10.10.0.1 dev veth-private
10.10.0.0/24 dev veth-private proto kernel scope link src 10.10.0.2
Ping Test (Public ↔ Private)
sudo ip netns exec vpc1-public ping -c 2 10.10.0.2
Internet Connectivity (via NAT)
sudo ip netns exec vpc1-public ping -c 2 8.8.8.8
(works only if host Internet and NAT are active)

Makefile Commands Overview
Command Description
make all Builds and tests all VPCs with subnets.
make vpc1 Creates VPC1 with public and private subnets.
make vpc2 Creates VPC2 with public and private subnets.
make clean Removes all VPC namespaces, bridges, and iptables rules.
Example Output (abridged)

Creating VPC 'vpc2' with bridge 'br-vpc2'...
IP forwarding enabled.
NAT configured for outbound traffic via wlp2s0
Bridge 'br-vpc2' created and ready.
Adding public and private subnets to vpc2...
Subnet vpc2-public added with IP 10.20.0.1/24
Subnet vpc2-private added with IP 10.20.1.1/24
VPC2 setup complete.
Cleanup
To delete all configurations and restore your host networking:

make clean
This removes:

All network namespaces (ip netns delete)

All VPC bridges

Related veth pairs

NAT and iptables rules

Notes

The project uses hardcoded CIDRs (10.10.0.0/16, 10.20.0.0/16, etc.) for clarity. These can be customized in the Makefile or passed as CLI arguments.

Works best on Ubuntu/Debian-based systems with systemd networking.

Run all commands with sudo for full permissions.

DEV Community: Chisolum Odoabuchi

VPC creation on Linux