Letsencrypt

# Install Certbot.

apt -y install certbot

# Create certificate for the given domain(s).

certbot certonly --webroot -w /var/nginx/share/html/ph-eu.dev -d ph-eu.dev

# Check timer and service.

systemctl list-timers certbot.timer --no-pager
systemctl status certbot.timer
systemctl cat certbot.timer
systemctl cat certbot.service

# For manual update, do:

certbot renew

# In case you get error like "Could not bind TCP port 80 because it is already in use by another process on this system...":

# Stop nginx.

service nginx stop

# Run Certbot to obtain the certificate.

certbot certonly --standalone -d ph-eu.dev

# Restart the web server.

service nginx start