Suppose, a server hosts
and thus is equipped with a (single domain) SSL certificate.
Furthermore, suppose there are some web apps below
http://wiki.master.com/ http://docs.master.com/ http://cal.master.com/ ...
To protect those web apps, one could use a wildcard certificate for
master.com, which reaches 1 level down. This wildcard SSL certificate would thus protect connections to each of these web apps.
Question: Could this wildcard certificate be issued, although another (non-wildcard) certificate for www.master.com has already been issued?
Do CAs exchange data to ensure, that the domains of issued certificates do not overlap?