Server 2016 DNS: The server forwarders cannot be updated, ip address is invalid .. but they are and no real change? Forwarders vanish from before too?

Posted by jimlaman8c@reddit | sysadmin | View on Reddit | 2 comments

I was trying to add dns forwarders to our forwarders tab of our one dns server on one of the two DC's in this network.

If i nslookup the ip, it resolves, the ip is valid, even works on port 53

Add the ip, even if it validates it, hit ok, apply, it gives the error message cannot be updated , ip is invalid.

Actually we had 10 ips (local ips on the network) in here and they seemed to have gone poof (not sure how that can happen)?

As a second test, i just went in, noted the two existing ip forwarders (the two dc ips), changed the timeout on validation from 3 to 4 seconds and hit apply, same error message, and obviously these two are valid.

Anyone have any tips on things to look for? Or why this might be happening? Event logs look fine etc