Windows server trying to use IPv6 despite being turned off

Question

I have a server which needs to communicate with another server (both win 2k8r2). One of them recently had an IP address change, and I suspect that the IPv6 address that the AD DNS server holds is now invalid. Nevermind, I switched off IPv6 on both servers. Now when I try to ping one from the other, it resolves the name to an IPv6 address, so the ping (and other services) fail.

An nslookup resolves two IPv6 address and the IPv4 address. However, despite IPv6 being turned off (on both ends) it's still trying to use IPv6. Any ideas?

Answer 1

Nslookup resolving the IPv6 addresses means you still have AAAA records in your DNS server. Removing them will likely fix your problem assuming IPv6 is actually turned off on the servers (otherwise, they'll just get re-added).

In what way did you turn off IPv6? Did you simply unlink the protocol from the active NIC? Or did you use the DisabledComponents value in the service's registry area? While both should theoretically work, we generally use the DisabledComponents registry value because it affects all NICs on the machine. More info in KB929852