Creating Cert

Generate a new private key (RSA)

openssl genrsa -out privateKey.key 4096
openssl ecparam -genkey -name secp384r1 -out privateKey.key

Generate a new private key (ECC)

openssl ecparam -genkey -name secp384r1 -out privateKey.key

Generate a self-signed certificate

openssl req -x509 -sha256 -nodes -days 365 -key privateKey.key -out certificate.crt

Generate a CSR for an existing private key

openssl req -out CSR.csr -key privateKey.key -new

Generate a CSR based on an existing certificate

openssl x509 -x509toreq -in certificate.crt -out CSR.csr -signkey privateKey.key

Remove a passphrase from a private key

openssl rsa -in privateKey.pem -out newPrivateKey.pem