IPv6 and dcpromo


We've been having issues for the last week because dcpromo was failing across the VPN. We thought it was the firewall causing the problem, so we got a completely new firewall - no dice. We then tried a VPN within the site-to-site VPN, and it worked! Really weird. Dan checked the ports using portquery, and they matched up just fine, no errors there.

But when we did a dcpromo from a remote site in, the dcpromo would fail at the replication stage - it would time out and say 'RPC call ended'. Keep in mind this machine was able to join the domain just fine.

So while on hold with Microsoft, we check the error logs, and nothing shows up. Then Dan starts checking the network settings, and BOOM! Lo and behold the DCs in our site have IPv6 disabled, and the server we're trying to bring up to DC status HAS IPv6 enabled!!!

Disabled it, tried the dcpromo again, worked! It was promoted in 30 seconds...used to take 5 minutes to time out.

When the lady came back to inform me that someone would be calling us back, I told her we fixed it. I then mentioned that perhaps the tech would like to speak to us for details on how this happened. She said sure, but if it turned out to be our fault, they would charge us the $300 for a support call. I passed, and posted the info here.

Pretty fancy that a default option would cause something as important as dcpromo to fail!!


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