How to make blog run in subdomain?

[jhon13]

Hello,

currently my forum is running on subdomain.
forum.mydomain.com

and i want to turn Blog on.
but on my navbar, it is redirecting to forum.mydomain.com/blog.php

is it possible to have blog on a subdomain too? like my forum?
for example.

blog.mydomain.com

if so, how is this possible to do so?
i tried putting http://blog.mydomain.com on Blog Component URL option on settings.
and it does change the redirect url, but it gives error. basically because there is nothing on that folder. So any step-by-step on how to actually do this? or this is not possible? i'm running 4.1.11 version of vbulletin for testing.