[root@CentOS7-copy tmp]# openssl req -days 3650 -x509 -sha256 -nodes -newkey rsa:2048 -keyout mansur.key -out mansur_apple.crt Generating a 2048 bit RSA private key ....+++ .........................................................................................................................+++ writing new private key to 'mansur.key' ----- You are about to be asked to enter information that will be incorporated into your certificate request. What you are about to enter is what is called a Distinguished Name or a DN. There are quite a few fields but you can leave some blank For some fields there will be a default value, If you enter '.', the field will be left blank. ----- Country Name (2 letter code) [XX]:CN State or Province Name (full name) []:Beijing Locality Name (eg, city) [Default City]:Chaoyang Organization Name (eg, company) [Default Company Ltd]:NBMABLOG Organizational Unit Name (eg, section) []:Net Common Name (eg, your name or your server's hostname) []:nbma.info Email Address []:i@nbma.info