I have a Windows 2016 server acting as a DHCP and DNS server for a small network. I have it configured such that when a client gets DHCP, it adds the client to DNS as well. This works great for the local subnet, but for the two subnets that go through a DHCP Relay Agent (A Cisco router in this case), no DNS entry is created for the client.
The Scope properties are configured identically, and I've tried it with and without "Always Dynamically Update DNS records", with the same result. I've setup the Credentials for the DHCP server, no change there either.
The clients get DHCP just fine, their DNS server is pointed to the same server that is also the DHCP server. There are no firewall rules blocking traffic between the subnets. I'm at a loss.