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Re: Repotting report

  • From: Kevin Loch
  • Date: Mon Feb 04 20:04:49 2008


Leo Bicknell wrote:
I have been using queries like these to test:

dig any . @f.root-servers.net | egrep "(DiG 9|AAAA)"
dig +bufsize=1400 any . @f.root-servers.net | egrep "(DiG 9|AAAA)"

The first offers up a standard DNS query, the second an EDNS0 query of
1400 bytes.

In a standard query you're only going to get 3 AAAA records, EDNS0
should allow for all of them.  There are currently 6 servers with AAAA
records:

% dig any . @f.root-servers.net | egrep "(DiG 9|AAAA)"
; <<>> DiG 9.5.0b2 <<>> any . @f.root-servers.net
A.ROOT-SERVERS.NET.	3600000	IN	AAAA	2001:503:ba3e::2:30
F.ROOT-SERVERS.NET.	3600000	IN	AAAA	2001:500:2f::f
H.ROOT-SERVERS.NET.	3600000	IN	AAAA	2001:500:1::803f:235

There is an interesting variation in what records are returned for a standard 512 byte request (dig ns . @[x].root-servers.net):

A,C,D,E,F,G,I,J: return the same 10 A records and 4 AAAA records in the
same order every time.  They never return A records for K,L,M and never
get AAAA records for K,M.

B: returns all 13 A records in random order and then two AAAA records
in random order.  This allows all records to be returned with equal
weight within each record type.

H,K,L,M: return all 13 A records in static order and then A and F AAAA
records so H,J,K,M AAAA records are never returned.

Tested with dig 9.4.1-p1 on a v6 enabled system.

- Kevin