We use a mix of Meraki L3 and Cisco ISRs in our environment to perform our routing and to also function as DHCP servers for our various locations.
We also have a MS Active Directory environment running on Windows domain controllers, which provide internal DNS services for the network. We also have Umbrella virtual appliances in the environment for DNS inspection and external resolution.
PCs in our network receive both their IP addresses and DNS server information from the requisite device (Meraki L3 or Cisco ISR) at their location. The DHCP assignment tells the PCs to use one of the Umbrella VAs as their primary DNS, and one of the other Umbrella VAs as the secondary.
The issue we have had forever that we can't figure out is why the PTR record for PCs is inconsistently created in the DNS table on the DCs. Sometimes the record is created, but sometimes it just isn't.
This causes issues because of a service we utilize which checks *both* the forward and reverse lookups to verify whether a PC can access the service. If the PTR records is absent, the user is unable to access the service from that PC.
The fix is to manually access the forward lookup record for the PC, and force create the PTR record. This isn't a world ender, but it certainly is annoying.
Any suggestions on what we may be missing here?
Thanks!
