nova@ubuntu:~$ openssl req -x509 -nodes -days 3650 -newkey rsa:2048 -keyout mykey.key -out mycert.pem
Generating a 2048 bit RSA private key
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writing new private key to 'mykey.key'
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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.
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Country Name (2 letter code) [AU]:KR
State or Province Name (full name) [Some-State]:.
Locality Name (eg, city) []:.
Organization Name (eg, company) [Internet Widgits Pty Ltd]:.
Organizational Unit Name (eg, section) []:.
Common Name (e.g. server FQDN or YOUR name) []:.
Email Address []:.