Unable to get AAAA for www.revk.uk from some of our servers

[Frank Bulk]

Thanks, Mark.

When I queried for the AAAA of ghs.l.google.com from ns[1-4].google.com the
Google servers reported they don't do recursive queries.  Which Google
namserver does in fact carry the authoritative records for ghs.l.google.com?

On a side note, I thought that Google's DNS servers were dual-stacked, but
that does not seem to be the case.  None of the ns[1-4].google.com servers
return an AAAA for me.  When I query the IPv6 interface of our recursive DNS
servers using "dig AAAA ghs.l.google.com +trace @[IPv6_address]" they all
return "connection timed out; no servers could be reached.  Here's an
example:

============================================
DNS server: 2607:fe28:0:1000::8

; <<>> DiG 9.7.3 <<>> -6 AAAA ghs.l.google.com +trace @2607:fe28:0:1000::8
;; global options: +cmd
.                       420917  IN      NS      c.root-servers.net.
.                       420917  IN      NS      k.root-servers.net.
.                       420917  IN      NS      f.root-servers.net.
.                       420917  IN      NS      b.root-servers.net.
.                       420917  IN      NS      g.root-servers.net.
.                       420917  IN      NS      a.root-servers.net.
.                       420917  IN      NS      d.root-servers.net.
.                       420917  IN      NS      j.root-servers.net.
.                       420917  IN      NS      i.root-servers.net.
.                       420917  IN      NS      h.root-servers.net.
.                       420917  IN      NS      l.root-servers.net.
.                       420917  IN      NS      e.root-servers.net.
.                       420917  IN      NS      m.root-servers.net.
;; Received 496 bytes from 2607:fe28:0:1000::8#53(2607:fe28:0:1000::8) in 0
ms

com.                    172800  IN      NS      e.gtld-servers.net.
com.                    172800  IN      NS      f.gtld-servers.net.
com.                    172800  IN      NS      k.gtld-servers.net.
com.                    172800  IN      NS      a.gtld-servers.net.
com.                    172800  IN      NS      l.gtld-servers.net.
com.                    172800  IN      NS      i.gtld-servers.net.
com.                    172800  IN      NS      g.gtld-servers.net.
com.                    172800  IN      NS      b.gtld-servers.net.
com.                    172800  IN      NS      h.gtld-servers.net.
com.                    172800  IN      NS      d.gtld-servers.net.
com.                    172800  IN      NS      c.gtld-servers.net.
com.                    172800  IN      NS      j.gtld-servers.net.
com.                    172800  IN      NS      m.gtld-servers.net.
;; Received 506 bytes from 2001:7fe::53#53(i.root-servers.net) in 113 ms

google.com.             172800  IN      NS      ns2.google.com.
google.com.             172800  IN      NS      ns1.google.com.
google.com.             172800  IN      NS      ns3.google.com.
google.com.             172800  IN      NS      ns4.google.com.
;; Received 170 bytes from 2001:503:a83e::2:30#53(a.gtld-servers.net) in 150
ms

;; connection timed out; no servers could be reached
============================================

-----Original Message-----
From: Mark Andrews [mailto:marka at isc.org] 
Sent: Tuesday, December 23, 2014 6:01 PM
To: Frank Bulk
Cc: bind-users at isc.org
Subject: Re: Unable to get AAAA for www.revk.uk from some of our servers


In message <001301d01f06$aa1c7180$fe555480$@iname.com>, "Frank Bulk" writes:
> I dumped the database of one failing server and found this entry:
> 
> ; authauthority
> ghs.l.google.com.       331     \-AAAA  ;-$NXRRSET
> ; l.google.com. SOA ns4.google.com. dns-admin.google.com. 1577084 900 900
> 1800 60
> ; authanswer
>                         289     A       74.125.201.121
> ;
> 
> What does the "\-AAAA   ;-$NXRRSET" mean?

It means that there is a negative cache entry for AAAA lookup.  The
SOA record that will be returned is in the comment.  For responses
from signed zones you will also see NSEC / NSEC3 records in the
comments as well as RRSIG.

NXRRSET (No Such RRset).
NXDOMAIN (No Such Domain).

> Working server shows this in the dump:
> ; authanswer
> ghs.l.google.com.       287     AAAA    2607:f8b0:4001:c08::79
> ;
> 
> Regards,
> 
> Frank Bulk
-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka at isc.org