DNS caching servers now listen on IPv6


#1

Hello everyone

Our caching nameservers now listen on both IPv4 and IPv6. Your resolv.conf can now contain:

[ulist]
[] 80.68.80.24
[
] 80.68.80.25
[] 2001:41c8:2::1
[
] 2001:41c8:2::2
[/ulist]

Note this is caching not content DNS!

Have fun!

Patrick


#2

Thanks - it’s good to see visible progress :slight_smile:

Interestingly the minimum response time I’m seeing from the IPv6 DNS servers is ~7ms, but for the IPv4 servers it’s ~1ms. Ping times match. Are they the same servers? Is there something unusual in the networking? I don’t see that response time difference for your v4/v6 NTP servers (both protocols respond in ~1ms).

Cheers,
Dave


#3

We use anycasting to direct the traffic between four boxes, each of which can answer on an any of the addresses. Two of the boxes are in Manchester, and two are in London.

The 7ms vs 1ms is probably the query going to one of the two boxes in London, rather than Manchester.


#4

Yes, I can confirm that the anycasting is only setup to go down to London at the moment. We’re waiting for our bgpfeeder software to support IPv6 for this to be properly fixed.


#5

Understood - thanks for the explanation.