How to Setup HAProxy as Load Balancer for Http on CentOS 8

SHORT INTRODUCTION

An SSL certificate for Secure Socket Layer is used to secure and secure communications between the browser and the server. An SSL certificate is also known as a digital certificate. An SSL connection protects sensitive data such as us credit card information and passwords that are validated during each visit. When you buy an SSL certificate from a trusted third party they will say that your SSL certificate is valid and legally used by its owners.

We need one Haproxy-server(192.168.33.25) & two client-server: client1(192.168.33.30) & client2(192.168.33.31), Make sure all are accessible

Step 1: Install the Apache Server on both Client Servers :

[root@client ~]# yum install httpd -y

Start & Enable their Services:

[root@client ~]# systemctl start httpd
[root@client ~]# systemctl enable httpd
[root@client ~]# systemctl status httpd

Now, need to create test pages that we will use later on to test out the HAProxy setup :

--- Client Server 1 ---
[root@client1 ~]# vim  /var/www/html/index.html
< h1> This is Fosnix's Client Server 1 < /h1>
--- Client Server 2 ---
[root@client2 ~]# vim  /var/www/html/index.html
< h1> This is Fosnix's Client Server 2 < /h1>

For Testing: Open your browser and Type your Client’s Server-IP as shown below-

Step 2: Installing and Configuring HAProxy Server on CentOS 8

[root@fosnix ~]# yum install haproxy -y

Start & Enable their Services:

[root@fosnix ~]# systemctl start haproxy

[root@fosnix ~]# systemctl enable haproxy

Now install & configure rsyslog –

[root@fosnix ~]# yum install rsyslog -y

[root@fosnix ~]# vim /etc/rsyslog.conf

Search & uncomment the below lines:

$ModLoad imudp

$UDPServerRun 514

Add the below lines in the same file

# HAProxy Logging

local2.* /var/log/haproxy.log

Save & Exit

Restart the rsyslog service

[root@fosnix ~]# systemctl restart rsyslog

Now, Configure Haproxy file

[root@fosnix ~]# vim /etc/haproxy/haproxy.cfg

Add the below lines in the file
In Stats auth fosnix:admin@123 replace fosnix with your username and admin@123 with your password

# HAProxy Load Balancer for Apache Web Server
frontend http-balancer
bind 192.168.33.25:80
default_backend web-servers
backend web-servers
mode http
balance roundrobin
stats enable
stats auth fosnix:admin@123
server client1 192.168.33.30:80 check
server client2 192.168.33.31:80 check

Now, Restart the Haproxy

[root@fosnix ~]# systemctl restart haproxy

If your firewall is on then allow the HTTP Services by the below commands:

[root@fosnix ~]# firewall-cmd --permanent --add-service=http
[root@fosnix ~]# firewall-cmd --permanent --add-service=https
[root@fosnix ~]# firewall-cmd --reload

Now, Open your browser and Type your Haproxy Server-IP with port “:80”, eg – http://192.168.33.25:80 as shown below-