letsencrypt

git clone https://github.com/certbot/certbot
cd certbot
./certbot-auto certonly -a standalone -d dragonet.org -d auth.dragonet.org

openssl pkcs12 -export -in fullchain.pem -inkey privkey.pem -out keystore.p12 -name cls -CAfile chain.pem -caname root
# every 90 days
sudo ./certbot-auto renew