We have two Exchange 2010 Hub Transport/CAS/Mailbox servers in separate sites and one 2010 Edge server. Currently, autodiscover.domain1.com is configured for the autodiscover URL on one server, and autodiscover.domain2.com is configured for the other. All SSL certs, split brain DNS, MX records, etc. are already established for this setup.
I'm getting ready to install 2013 for the domain1 location. Immediately following the installation, I need to configure the autodiscover URLs on that server. Is it proper to use the already established url, autodiscover.domain1.com along with a new DNS host record for autodiscover pointing to the internal IP of the new server, or does a new, unique autodiscover name need to be used and added as a new SAN to our SSL certificate?