About the Author

I'm Carrie, a cybersecurity engineer and writer, working for SafeLine Team. SafeLine is a free and open source web application firewall, self-hosted, very easy to use.

Introduction

In today's digital world, securing your website is paramount to protect user data and maintain trust. One essential step in securing a website is implementing HTTPS, which encrypts the data transmitted between a user's browser and your server. Certbot is a popular tool that simplifies the process of obtaining and renewing SSL/TLS certificates from Let's Encrypt, making it easier to secure your website. This guide will explain what Certbot is, how it works, and how you can use it to secure your website.

What is Certbot?

Certbot is a free, open-source software tool for automatically using Let's Encrypt certificates on websites to enable HTTPS. Let's Encrypt is a certificate authority that provides free SSL/TLS certificates, and Certbot automates the process of obtaining, installing, and renewing these certificates.

Why Use Certbot?

Here are some key reasons to use Certbot for your website:

1. Free SSL Certificates: Certbot, in conjunction with Let's Encrypt, provides free SSL/TLS certificates, helping you save on the cost of securing your website.
2. Automation: Certbot automates the process of obtaining and renewing certificates, reducing the administrative burden and ensuring your site remains secure.
3. Ease of Use: Certbot is designed to be user-friendly, even for those who are not experts in web security.
4. Improved Security: By enabling HTTPS, Certbot helps protect your users' data and improve your site's security and trustworthiness.

How Does Certbot Work?

Certbot works by interacting with the Let's Encrypt certificate authority to obtain and install SSL/TLS certificates. Here is a simplified overview of the process:

1. Request Certificate: Certbot sends a request to Let's Encrypt for a new certificate.
2. Domain Validation: Let's Encrypt verifies that you control the domain for which you are requesting a certificate. This is typically done through DNS or HTTP validation.
3. Certificate Issuance: Once the domain is validated, Let's Encrypt issues the SSL/TLS certificate.
4. Installation: Certbot installs the certificate on your web server, configuring it to use HTTPS.
5. Automatic Renewal: Certbot can be set up to automatically renew the certificate before it expires, ensuring continuous protection.

How to Use Certbot

Step 1: Install Certbot

Certbot can be installed on various operating systems. Below are the commands for some common environments:

On Ubuntu/Debian:

sudo apt update
sudo apt install certbot python3-certbot-nginx

On CentOS/RHEL:

sudo yum install epel-release
sudo yum install certbot python2-certbot-nginx

Step 2: Obtain and Install a Certificate

Once Certbot is installed, you can use it to obtain and install a certificate. Here is an example for an Nginx server:

sudo certbot --nginx

Certbot will guide you through the process, including selecting the domains you want to secure and configuring your web server to use HTTPS.

Step 3: Set Up Automatic Renewal

To ensure your certificates are always up to date, set up automatic renewal with a cron job. Certbot’s certificates are valid for 90 days, so it’s important to renew them regularly.

Open the crontab file:

sudo crontab -e

Add the following line to run the renewal twice a day:

0 0,12 * * * /usr/bin/certbot renew --quiet

Conclusion

Certbot is a powerful tool that simplifies the process of securing your website with HTTPS. By automating the acquisition and renewal of SSL/TLS certificates from Let’s Encrypt, Certbot helps you enhance your website’s security, protect user data, and maintain trust. Whether you’re a seasoned web administrator or just starting, Certbot is an invaluable resource for implementing HTTPS on your site.