Obtain and renew letsencrypt ssl certificate via certbot

get_letsencrypt.sh

#!/bin/bash
# Inspired by an earlier version of Matthieu Petiteau's scripts at  https://github.com/smallwat3r

echo "------------------------------------------------------" \
     "\nThis script is intended for Ubuntu/Debian Linuxes." \
     "\nIt needs to be run as root, on the server which DOMAIN points at." \
     "\nIt installs the letsencrypt client and gets/renews a certificate" \
     "\nfor the specified domain and email address." \
     "\n------------------------------------------------------"
export EMAIL=you@mailbox.org
export DOMAIN=yourdomain.com

apt update && apt install -y snapd ufw
snap install core
snap refresh core
snap install --classic certbot
ln -s /snap/bin/certbot /usr/bin/certbot
ufw allow 80
certbot certonly --renew-by-default --standalone --email $EMAIL -d $DOMAIN --agree-tos --eff-email
ufw deny 80

echo "Job finished."