Pour créer une clé privée RSA (ici 4096 bits) :
openssl genrsa -out example.rsa.key 4096
Pour créer une clé privée
openssl ecparam -genkey -name secp384r1 | openssl ec -out example.ec.key
sudo openssl req -new -key /etc/ssl/private/example.ec.key -out example.csr -sha256
sudo certbot-auto certonly --server https://acme-v02.api.letsencrypt.org/directory --manual --csr /etc/letsencrypt/grohub.pro/grohub.pro.csr --cert-path /etc/letsencrypt/grohub.pro/grohub.pro.crt --register-unsafely-without-email
openssl dhparam -out /etc/ssl/dhparam.pem 4096
openssl rand 48 > /etc/ssl/ticket.key
openssl rsa -in server.key -out decrypted.key
sudo openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout /etc/ssl/private/domain-selfsigned.key -out /etc/ssl/certs/domain-selfsigned.crt