DNS - request route | How to resolve a subset from the internet??

Question

Hi everyone, 
 i have a change request that some domain names should not be resolved from an internal DNS server but all others should. This setup is necessary so that one application can work (Skype for Business). 
 Say we have a partner contract with CompanyA - there are many services like citrix, webmail etc that we are using from this company. My IT department does not know about these services - just responsible for the VPN connection and the DNS resolution. 
 Now we have to configure that 
 appvalley skype.companyA.com skypeSIP.companyA.com skypeweb.companyA.com (and 30 others) 
 should not be resolved from the internal CompanyA DNS server but the external DNS servers. 
 Is there any way to set an exception list or do i have to create all network definitions (and keep em updated) at the UTM with the corresponding external internet IPs? (which is the only possiblity i found yet) 
 Thanks for your help

PhilippRusch · Answer

Hi Ollie, 
 you are talking about DNS. So you could setup things like this: 
 if all DNS records resolve to CompanyA.com, then have a policy route pointing to their DNS and that&lsquo;s it! 
 Every subdomain will then correctly be resolved, if the other DNS has an entry for it. 
 Go to Network Services/DNS/Request Routing and setup your DNS entry there.