Let's Encrypt is a free, automated, and open certificate authority (CA). It is a service provided by the Internet Security Research Group (ISRG). It gives people the digital certificates they need in order to enable HTTPS (SSL/TLS) for websites, for free. Let's Encrypt is free, automatic, secure, and open.

  How to Install Let's Encrypt on Ubuntu Linux VPS to Create SSL Certificates

Downloading and Installing Let's Encrypt

1. Log into your Ubuntu VPS and update the server's packages

apt-get update & sudo apt-get upgrade

2. Install the GIT package

apt-get install git

3. Download a clone of Let's Encrypt from the GitHub repository. It is common practice to install third-party packages to /opt, so let's install it there

git clone https://github.com/letsencrypt/letsencrypt /opt/letsencrypt

4. Navigate to the new /opt/letsencrypt directory

cd /opt/letsencrypt

Creating an SSL Certificate

1. Run Let's Encrypt for your domain requiring a certificate

./letsencrypt-auto certonly --standalone -d example.com -d www.example.com

2. Specify an email address to regain control of a lost certificate and receive urgent security notices

3. Agree to the Terms of Service

4. If everything worked properly, you should receive a message similar to the following