How to use Let’s Encrypt for NGINX on Ubuntu

Let’s Encrypt is an SSL certificate authority managed by the Internet Security Research Group.

Web server NGINX is a free, open-source, high-performance HTTP server.

You can use HTTPS (an extension of HTTP with SSL / TLS encryption) on your website to secure connection.

Install packages:

apt update
apt install -y \
    python-software-properties software-properties-common 
add-apt-repository ppa:certbot/certbot 
apt update apt install -y \
    certbot 

Add the location for Let’s Encrypt in server section of your site’s nginx config:

server {
    ...
    # Let's Encrypt
    location ^~ /.well-known/acme-challenge/ {
        root /path/to/static/;
        add_header Cache-Control public;
        allow all;
    }
    ...
} 

Reload nginx configuration

systemctl reload nginx

Get certifies from Let’s Encrypt

certbot certonly -a webroot \
    --webroot-path=/path/to/static/ \
    -d DOMAIN_NAME -d www.DOMAIN_NAME 

/path/to/static/ is the same directory which we define in nginx config.

Enable https in NGINX config:

server {
    listen 443 ssl;
    server_name DOMAIN_NAME www.DOMAIN_NAME;
    # SSL cert
    ssl_certificate /etc/letsencrypt/live/DOMAIN_NAME/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/DOMAIN_NAME/privkey.pem;
    # Let's Encrypt location
    ^~ /.well-known/acme-challenge/ {
        root /path/to/static/;
        add_header Cache-Control public;
        allow all;
    }
    ...
    # Here you can place your locations.
} 

Reload nginx configuration

systemctl reload nginx