[Pdns-users] Per-record packet cache override

[Jonathan Thorpe]

Hi All,

I have been looking at implementing the GeoIP backend for PowerDNS and noticed that in order to be effective, the packet and query cache needs to be disabled. I have a few ideas for other custom back-ends that I'd like to explore as well, all of which rely on unique responses for each request.

If I'm not mistaken, there are currently two ways to achieve this:
1. Disable packet caching all together.
2. Run a separate instance of PowerDNS.

The first option probably isn't a good idea for this particular implementation as we appear to get a fairly good hit rate with the packet cache and the DNS servers are otherwise very busy. The second option is fine, but because you can't implement a CNAME on the zone apex, it represents a challenge for us.

Are there any other options people employ to overcome this?

What I'd ideally like to do is somehow signal to the packet cache not to attempt to cache specific records so that they're retrieved fresh each time. Is there a mechanism in PowerDNS that exists to do this?

Kind Regards,
Jonathan