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🌐 Simple Web Load Balancer Using Vagrant and HAProxy

#loadbalancer #vagrant #devops #crosscloudx

🛠 Introduction

Load balancers help distribute traffic across multiple servers, improving performance, availability, and scalability. In this guide, we’ll set up a simple web load balancer using Vagrant, VirtualBox, and HAProxy.

We will:

✅ Set up two web servers using Nginx
✅ Deploy HAProxy to balance traffic
✅ Test load balancing with Apache Benchmark (ab)
✅ Enable HAProxy Stats Page for monitoring

🚀 Let’s get started!

loadbalancer-v1

📂 Project Structure 

load-balancer-demo/ │── Vagrantfile │── provisioning/ │ ├── haproxy.sh │ ├── webserver.sh
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🏗 Step 1: Install Vagrant & VirtualBox

First, install Vagrant and VirtualBox on your system:

🔹 Download & Install:

Vagrant
VirtualBox

Once installed, check versions:

vagrant --version VBoxManage --version
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⚙️ Step 2: Create a Vagrantfile

In your project folder (load-balancer-demo/), create a file named Vagrantfile and add:

Vagrant.configure("2") do |config| # Web Server 1 config.vm.define "web1" do |web1| web1.vm.box = "ubuntu/focal64" config.vm.box_version = "20240821.0.1" web1.vm.network "private_network", ip: "192.168.56.11" web1.vm.provision "shell", path: "provisioning/webserver.sh" end # Web Server 2 config.vm.define "web2" do |web2| web2.vm.box = "ubuntu/focal64" config.vm.box_version = "20240821.0.1" web2.vm.network "private_network", ip: "192.168.56.12" web2.vm.provision "shell", path: "provisioning/webserver.sh" end # HAProxy Load Balancer config.vm.define "haproxy" do |haproxy| haproxy.vm.box = "ubuntu/focal64" config.vm.box_version = "20240821.0.1" haproxy.vm.network "private_network", ip: "192.168.56.10" haproxy.vm.provision "shell", path: "provisioning/haproxy.sh" end end
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🌐 Step 3: Provision Web Servers

Create a provisioning script for Nginx Web Servers:

📄 provisioning/webserver.sh

#!/bin/bash sudo apt update && sudo apt install -y nginx echo "<h1>Web Server $(hostname -I | awk '{print $2}')</h1>" | sudo tee /var/www/html/index.html sudo systemctl restart nginx
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This script installs Nginx and creates a basic webpage showing the server name.

⚖️ Step 4: Provision HAProxy Load Balancer

📄 provisioning/haproxy.sh

#!/bin/bash sudo apt update && sudo apt install -y haproxy # HAProxy Configuration cat <<EOF | sudo tee /etc/haproxy/haproxy.cfg frontend http_front bind *:80 default_backend web_servers backend web_servers balance roundrobin server web1 192.168.56.11:80 check server web2 192.168.56.12:80 check EOF sudo systemctl restart haproxy
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This config:
✅ Listens on port 80
✅ Balances traffic between two web servers

🚀 Step 5: Start the Virtual Machines

Run the following command to start all virtual machines:

vagrant up
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❯ vagrant status Current machine states: web1 running (virtualbox) web2 running (virtualbox) haproxy running (virtualbox) This environment represents multiple VMs. The VMs are all listed above with their current state. For more information about a specific VM, run `vagrant status NAME`.
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To check the HAProxy load balancer:

curl http://192.168.56.10
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💡 You should see alternating responses from Web Server 1 and Web Server 2.

responses

📊 Step 6: Generate Traffic with Apache Benchmark (ab)

Run the following command to simulate 1000 requests with 20 concurrent users:

ab -n 1000 -c 20 http://192.168.56.10/
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📋 Example Output:

Concurrency Level: 20 Time taken for tests: 2.345 seconds Complete requests: 1000 Failed requests: 0 Requests per second: 426.45 [#/sec]
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🔹 This confirms HAProxy is distributing traffic correctly!

📡 Step 7: Enable HAProxy Stats Page

📄 Add this to haproxy.sh before restarting HAProxy:

listen stats bind *:8080 stats enable stats uri /stats stats refresh 5s stats auth admin:password
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Restart HAProxy:

vagrant reload --provision
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Now visit http://192.168.56.10:8080/stats and log in with:

haproxy-stats

Here, you can monitor:
✅ Requests per second
✅ Active connections
✅ Server health

❌ Step 9: Destroy Everything

When you're done, clean up everything with:

vagrant destroy -f
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vagrant-destroy

🎉 Final Thoughts

🚀 Now you have:
✅ A working HAProxy load balancer
✅ Traffic simulation using Apache Benchmark
✅ A real-time monitoring UI

💡 Next Steps?

Try different balancing algorithms (roundrobin, leastconn, source)
Test with more web servers
Deploy it on a real cloud environment

1️⃣ Clone the repository: 

git clone https://github.com/francotel/loadbalancer-haproxy-vagrant.git cd loadbalancer-haproxy-vagrant vagrant up
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🤝 Let's Connect!

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Thank you for reading! 😊

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