In this tutorial, we are going to setup Let’s Encrypt SSL (free SSL) on CentOS 8 / RHEL 8 server running Apache webserver.

Table of Contents

1. Install Certbot – Let’s Encrypt Client
2. Generate SSL Certificate
3. Setup Auto-renewal
4. Check Certificate Status
5. Delete Certbot Certificate

Step 1 : Install Certbot – Let’s Encrypt Client

At first, we need to install mod_ssl & epel-release:

sudo dnf install -y epel-release mod_ssl

If you’re using firewall, then open HTTPS port. I’m showing for firewalld:

# open port
firewall-cmd --permanent --add-port=443/tcp

# reload
firewall-cmd --reload

Now let’s install Certbot:

sudo dnf install certbot python3-certbot-apache

Step 2 : Generate SSL Certificate

We have the necessary modules to generate Let’s Encrypt SSL. To generate certificate for a single domain, run this command:

certbot --apache -d example.com

To generate SSL for multiple domains or subdomains, run this command:

certbot --apache -d example.com -d www.example.com

Here, example.com is the base domain.

You can also generate an SSL certificate by choosing a domain name. To do this, run this command to show all hosted domains:

certbot --apache

Choose one option and run that command what you needed. After successful installation, you will see a message similar to this message:

IMPORTANT NOTES:
 - Congratulations! Your certificate and chain have been saved at:
   /etc/letsencrypt/live/example.com/fullchain.pem
   Your key file has been saved at:
   /etc/letsencrypt/live/example.com/privkey.pem
   Your cert will expire on 2019-10-24. To obtain a new or tweaked
   version of this certificate in the future, simply run certbot again
   with the "certonly" option. To non-interactively renew *all* of
   your certificates, run "certbot renew"
 - If you like Certbot, please consider supporting our work by:

   Donating to ISRG / Let's Encrypt:   https://letsencrypt.org/donate
   Donating to EFF:                    https://eff.org/donate-le

Step 3 : Setup Auto-renewal

We know that Let’s Encrypt certificates are valid for 90 days. But we can renew the certificates very easily. Just run this command before the expiration date:

certbot renew

We can also setup a cronjob to renew automatically. Open the cronjob:

crontab -e

Then add this line:

0 0 * * * /usr/bin/certbot renew > /dev/null 2>&1

Step 4 : Check Certificate Status

We have successfully installed Let’s Encrypt SSL. Now let’s check the status of the SSL certificate by visiting this URL:

https://www.ssllabs.com/ssltest/analyze.html?d=example.com

Step 5 : Delete Certbot Certificate

To delete the certificate we have to run this command:

# to select domain name
certbot delete

# directly assign domain name
certbot delete --cert-name example.com

The article is over. Thanks for reading.