SSL Certificate Issue

Question

Eg I generated a CSR with domain: www.domain.com

If now i want to setup a SSL sub-domain with test.domain.com Do i need to generate another CSR for the certificate installation?

Or i can just reuse the previous CSR generated for www.domain.com?

Answer 1

You need a new Certificate.

Wildcard certificates
The Next time you can consider buying Wildcard certificates, that will do what you describe above. I was unable to find a good describtion online ( That was not on a vendors site).

So il do my best: Wildcard certificates allow you to buy for a whole domain like MyCompany.com, and then you can use unlimited amount of subdomains.

But there is restrictions:
1) Not all software support them, so make sure your web server and the application your gonna host does ( Dont think it will be a issue with web servers).
2) Not all client software supports it ( Mostly the issue where would epic old web browsers ( Older then IE 6 ) and Cell phones.
3) They can also support multiple physical servers
4) They are more expensive, so you should do the math.