DNSSEC and DNS timeouts

Hi,
after a while we noticed that our DNS resolution is not always fast as expected, so I tried few test using nslookup from my computer behind Omnia and noticed that resolving new DNS names often for the first time causes time out and following request for same name is immediately returned correctly, for example here for microsoft.co.uk domain:
> microsoft.co.uk.
Server: UnKnown
Address: fde2:58dd:b908::1

DNS request timed out.
    timeout was 2 seconds.
*** Request to UnKnown timed-out
> microsoft.co.uk.
Server:  UnKnown
Address:  fde2:58dd:b908::1

Non-authoritative answer:
Name:    microsoft.co.uk
Addresses:  23.101.184.206
          104.40.191.237
          104.43.142.34
          191.235.218.166
          191.237.78.58

So I’ve tried to disable DNSSEC validation in foris and after that I haven’t noticed any timeout any more, but as proposed by foris, I’d like to avoid completely disabling DNSSEC validation. Forwarding is in administration turned off.

Is there anything I can try to change in order to get rid of timeouts and keep DNSSEC validation enabled?

Thank you for any advice.

Vl.

Thank you. This domain really does take roughly 3 sec. to resolve on Omnia. We will look into the issue.

Forwarding would most likely avoid that delay, but forwarding before Omnia 3.8 won’t do (local) DNSSEC validation. Since upcoming 3.8 there will be kresd > 1.3 that does validate even when forwarding, by default.

Do I guess correctly that you don’t have working IPv6? I think I see what’s causing majority of the delay.

Yes, you are right.

As my current ISP does not support native IPv6 yet and SixXT closed their tunnels I am now on v4 only.

Vl.

And what about Hurricane electric … it is good solution for IPv6 tunneling.

@wladik: for now, you can use this workaround [SOLVED] Slow DNS resolution (no forwarding) when WAN is not active It should give you a noticeable speedup on most uncached queries.

I hope we can do this better in future on Omnia; I’ll try to push it.

@vcunat Thank you, it helped with DNS resolution. But as I started changing router configuration, as @Nones mentioned HE.net, I finally registered there and replaced my previous SixXS tunnel with the one from HE and with this IPv6 connectivity is DNS also working fast once again.

Thank you very much to both of you for help.

Vl.

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