$ openssl genpkey -algorithm RSA -pkeyopt rsa_keygen_bits :2048 -pkeyopt rsa_keygen_pubexp :65537 -out cakey.pem

$openssl req -new -x509 -key cakey.pem -out cacert.pem -days 1095

$Openssl genpkey -algorithm RSA -pkeyopt rsa_keygen_bits :2048 -pkeyopt rsa_keygen_pubexp :65537 -out privkey-www.exemple.com.pem

$openssl req -new -key privkey-www.exemple.com.pem -out certreqwww.exemple.com.csr

$Openssl ca -in certreq-www.exemple.com.csr -out cert-www.exemple.com.pem

$cp demoCA/cacert.pem cert-ourca.crt

$Openssl verify -CAfile cacert.pem cert-www.exemple.com.pem