How do I add an IP address SAN to a self signed Splunk certificate for security?

[tesme]

I tried editing ~openssl.conf ... dns.1 10.0.0.12

Obviously, I see the problem here with dns and it being an IP address. But, I don't know what to do from here. My setup is Splunk in a Ubuntu Virtualbox with an IP address. I don't think DNS is an option??