Load Balancer Solution With Apache

We will be using servers we configured for our tooling website which consists of:

1. Two RHEL8 Web Servers
2. One MySQL DB Server (based on Ubuntu 20.04)
3. One RHEL8 NFS server

Configure Apache As A Load Balancer

1. Set up a new Ubuntu server on EC2.
2. Install Apache Load Balancer on the server and configure it to point traffic coming to Load Balancer to both Web Servers:

# Install apache2
sudo apt update
sudo apt install apache2 -y
sudo apt-get install libxml2-dev

# Enable the following modules:
sudo a2enmod rewrite
sudo a2enmod proxy
sudo a2enmod proxy_balancer
sudo a2enmod proxy_http
sudo a2enmod headers
sudo a2enmod lbmethod_bytraffic

3. Restart apache2 service

sudo systemctl restart apache2

4. Make sure apache is running

sudo systemctl status apache2

5. Configure load balancing

sudo vi /etc/apache2/sites-available/000-default.conf

6. Add this configuration between section <VirtualHost *:80> and </VirtualHost> section:

<Proxy "balancer://mycluster">
        BalancerMember <WebServer1-Private-IP-Address>:80 loadfactor=5 timeout=1
        BalancerMember <WebServer2-Private-IP-Address> loadfactor=5 timeout=1
          roxySet lbmethod=bytraffic
        # ProxySet lbmethod=byrequests
 </Proxy>

        ProxyPreserveHost On
        ProxyPass / balancer://mycluster/
        ProxyPassReverse / balancer://mycluster/ 

7. Verify that our configuration works by accessing our LB’s public IP address or Public DNS name from the web browser

Unmount log directory

1. Remember we mounted /var/log/httpd/ from our Web Servers to the NFS server in our tooling project - unmount them and make sure that each Web Server has its own log directory.

sudo umount -l <WebServer-Private-IP-Address>:/mnt/logs

2. Open two ssh consoles for both Web Servers and run following command:

sudo tail -f /var/log/httpd/access_log

3. Refresh your browser page http://<Load-Balancer-Public-IP-Address>/index.php several times and make sure that both servers receive HTTP GET requests from your LB - new records must appear in each server’s log file.