- sed 's/my.domain.com/actual.domain.com/' server_csr.cnf.example > server_csr.cnf

- sed 's/my.domain.com/actual.domain.com/' v3.ext.example > v3.ext

- openssl req -new -sha256 -nodes -out my.domain.com.csr -newkey rsa:2048 -keyout my.domain.com.key -config server_csr.cnf

- openssl x509 -req -in my.domain.com.csr -CA rootCA.pem -CAkey rootCA.key -CAcreateserial -out my.domain.com.crt -days 500 -sha256 -extfile v3.ext