Installing HAProxy on Fedora 30/29

18/10/2025

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How to Install and Configure HAProxy on Fedora: A Comprehensive Guide

In the world of web infrastructure, ensuring high availability and reliability is paramount. HAProxy, a powerful and open-source solution, stands out as a leading high-performance TCP/HTTP load balancer and reverse proxy. By distributing web traffic across multiple servers, HAProxy prevents any single server from becoming a point of failure, dramatically improving the uptime and performance of your applications.

This guide provides a step-by-step walkthrough for installing and configuring HAProxy on Fedora Linux, transforming your single-server setup into a resilient, load-balanced architecture.

Prerequisites

Before we begin, ensure you have the following:

A system running a recent version of Fedora Linux.
Access to a user account with sudo or root privileges.
At least two backend web servers to balance traffic between (for testing purposes).

Step 1: Installing HAProxy on Fedora

The first step is to install the HAProxy package from Fedora’s default repositories. It’s always a best practice to update your system’s package index before installing new software.

Update Your System Packages: Open your terminal and run the following command to ensure all your existing packages are up to date.
bash sudo dnf update -y
Install HAProxy: Once the update is complete, install HAProxy using the dnf package manager.
bash sudo dnf install haproxy -y
Verify the Installation: After the installation finishes, you can verify that HAProxy is installed correctly and check its version.
bash haproxy -v
This command will output the installed version of HAProxy, confirming the installation was successful.

Step 2: Starting and Enabling the HAProxy Service

With HAProxy installed, the next step is to start the service and enable it to launch automatically on system boot. This ensures your load balancer will be active even after a server reboot.

Start the HAProxy Service: Use systemctl to start the HAProxy daemon.
bash sudo systemctl start haproxy
Enable HAProxy on Boot: To make the service persistent across reboots, enable it with this command.
bash sudo systemctl enable haproxy
Check the Service Status: You can confirm that the service is running without errors by checking its status.
bash sudo systemctl status haproxy
Look for an active (running) message in the output, which indicates the service is operating correctly.

Step 3: Configuring a Basic Load Balancer

The real power of HAProxy lies in its configuration file. This file, located at /etc/haproxy/haproxy.cfg, defines how traffic is received and where it is sent. Let’s configure a simple HTTP load balancer.

First, open the configuration file in a text editor like nano or vim:

sudo nano /etc/haproxy/haproxy.cfg

An HAProxy configuration is typically divided into four key sections: global, defaults, frontend, and backend.

global: Sets process-wide security and performance parameters.
defaults: Defines default parameters for all subsequent frontend and backend sections.
frontend: Describes a set of listening sockets that accept client connections.
backend: Describes a set of servers to which the proxy will forward incoming connections.

Here is a practical example configuration. You can replace the existing content or append this to your haproxy.cfg file.

global
    log       /dev/log local0
    chroot    /var/lib/haproxy
    pidfile   /var/run/haproxy.pid
    maxconn   4000
    user      haproxy
    group     haproxy
    daemon

defaults
    mode                    http
    log                     global
    option                  httplog
    option                  dontlognull
    option http-server-close
    option forwardfor       except 127.0.0.0/8
    option                  redispatch
    retries                 3
    timeout http-request    10s
    timeout queue           1m
    timeout connect         10s
    timeout client          1m
    timeout server          1m
    timeout http-keep-alive 10s
    timeout check           10s
    maxconn                 3000

# Frontend: How requests are received
frontend http_frontend
    bind *:80
    default_backend http_backend

# Backend: Where requests are sent
backend http_backend
    balance roundrobin
    server  web-01 192.168.1.10:80 check
    server  web-02 192.168.1.11:80 check

In this example:

The frontend named http_frontend listens for all incoming traffic on port 80.
It then forwards this traffic to the backend named http_backend.
The backend uses a roundrobin balancing algorithm, which distributes requests evenly across the defined servers.
Replace 192.168.1.10 and 192.168.1.11 with the actual IP addresses of your web servers. The check parameter enables health checks, so HAProxy will stop sending traffic to a server if it becomes unresponsive.

Step 4: Configuring Firewall and SELinux

By default, Fedora’s firewall and SELinux policies will block incoming web traffic. You must create rules to allow HAProxy to function correctly.

Allow HTTP Traffic Through the Firewall: If your frontend is listening on port 80, you need to allow the http service through firewalld.
bash sudo firewall-cmd --permanent --add-service=http sudo firewall-cmd --reload
If you are also load-balancing HTTPS traffic on port 443, run this as well:
bash sudo firewall-cmd --permanent --add-service=https sudo firewall-cmd --reload
Configure SELinux: SELinux may prevent HAProxy from binding to network ports. To allow this, you can set the appropriate SELinux boolean.
bash sudo setsebool -P haproxy_connect_any=1
The -P flag makes this change persistent across reboots.

Step 5: Validating and Applying Your Configuration

Before applying any changes, it is crucial to validate your configuration file for syntax errors. This simple step can prevent downtime.

Validate the Configuration File: Run the following command.
```
haproxy -c -f /etc/haproxy/haproxy.cfg
```
If the file is valid, you will see the message “Configuration file is valid”. If there are errors, the output will tell you which line is causing the issue.
Reload the HAProxy Service: Once validated, apply the new configuration by reloading the service. A reload is a graceful way to apply changes without dropping existing connections.
bash sudo systemctl reload haproxy

Your HAProxy load balancer is now live! You can test it by navigating to the public IP address of your HAProxy server in a web browser. Each time you refresh the page, your request should be served by a different backend server according to the roundrobin algorithm.

Source: https://kifarunix.com/setup-haproxy-load-balancer-on-fedora-30-fedora-29/