Install a Free SSL Certificate on a Linux VPS with Certbot

What you need

• A Linux VPS with Apache or Nginx already running.
• A registered domain whose DNS points to the VPS.
• SSH access with sudo rights.

Step 1: Update the system

sudo apt update && sudo apt upgrade

Step 2: Install Certbot

Install snapd first:

sudo apt install snapd && sudo snap install core

Then install Certbot:

sudo snap install --classic certbot

Link the command so it works everywhere:

sudo ln -s /snap/bin/certbot /usr/bin/certbot

Step 3: Get the certificate

For Apache:

sudo certbot --apache

For Nginx:

sudo certbot --nginx

Enter your email, accept the terms, choose your domain, and let Certbot set up the redirect to HTTPS.

Step 4: Check the result

Open your site with https:// and check the padlock in the browser.

Step 5: Auto-renewal

Let's Encrypt certificates last 90 days. The Snap package normally adds a renewal timer by itself. You can test it with:

sudo certbot renew --dry-run

If you prefer a cron job, open the crontab:

sudo crontab -e

and add a line that runs twice a day:

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

Quick recap

• Install snapd, then Certbot, and link the command.
• Run certbot --apache or certbot --nginx.
• Test renewal with certbot renew --dry-run.