Tomasz Kramkowski

The mystery DS record

So after transferring my domain from transip.eu to namecheap.com for WHOIS privacy I realised that suddenly the Google public DNS servers were no longer able to resolve my domain. Very quickly, I realised that quite a few things seemed to rely on the Google public DNS services (and DNSSEC supporting resolvers). Fun ensued.

DNSSEC is a fancy extension to DNS which allows resolvers to cryptographically confirm, through the use of some public keys and signatures, that the records they are looking up are in fact the records they want and not the result of some MITM attack. This is explained well in multiple places, so I won't explain it here.

I transferred my domain from transip.eu who provide DNSSEC (no way to publish DS records, everything is maintained in the background), but don't provide WHOIS privacy, to namecheap.com who do provide WHOIS privacy but don't provide DNSSEC. The DS record that transip.eu published to gtld-servers for their DNSSEC was left published after I transferred which initially, for someone who didn't know anything about DNSSEC, caused many confusing side effects.

DS records have to be published in the parent zone, this means that it has to be done through your registrar. (Unless you have a lot of money and time and feel like bribing Verisign. If someone knows how to do this without bribery, tell me!). Upon contacting namecheap about the issue, the person I was talking to seemed confused about the issue. They seemed to think I was having issues with A and AAAA records and DNS propagation. They tried to inform me that I just had to wait. Of course, all the waiting in the world wouldn't get the DS records to disappear so after explaining the situation a bit better (I still didn't quite know much about it myself) I got them to contact their "upstream DNS provider."

Finally, a weekend later, the DS record was gone and Google's DNS servers were serving my records again. Additionally, I switched over to using my own BIND name server so I could have full control over my DNS. This proved to be quite fun to set up. The second server is hosted by a good friend of mine and the third one by a friend of that friend. So far, other than me accidentally forgetting to enable named.service and rebooting my server to find that DNS wasn't working very well, I've had no problems.