Re: Internet-wide port scans

2012-10-16 Thread Bacon Zombie
Have a look at the talks done by Fyodor the creator of Nmap Scanning the
Internet.

http://nmap.org/presentations/BHDC08/bhdc08-slides-fyodor.pdf

http://www.securitytube.net/video/170

http://blog.thc.org/index.php?/archives/2-Port-Scanning-the-Internet.html

Also if you are look for a host CloudSigma are open to Security Researches
using their VPS system for this kind of work.

http://www.cloudsigma.com/




 On 16 Oct 2012 05:59, Scott Weeks sur...@mauigateway.com wrote:



 --- djahanda...@gmail.com wrote:
 From: Darius Jahandarie djahanda...@gmail.com

 Either way, in the US at least, it's not legal to port scan random
 machines on the internet, so this was a rather useless exercise. (And
 --


 Want to re-write that section or should I respond now?  ;-)

 scott




Search DSL Supplier in Italy

2012-10-16 Thread Olivier CALVANO
Hi

I am search good DSL (Adsl/Sdsl/EFM) supplier in Italy.
delivred in ATM, L2TP or EThernet Vlan (no internet)

Contact me

best regards
Olivier



Re: best way to create entropy?

2012-10-16 Thread JC Dill

On 11/10/12 5:01 PM, shawn wilson wrote:

in the past, i've done many different things to create entropy -
encode videos, watch youtube, tcpdump -vvv  /dev/null, compiled a
kernel. but, what is best? just whatever gets your cpu to peak or are
some tasks better than others?

You might want to take a look at:
http://www.lavarnd.org/news/lavadiff.html

jc



Re: Detection of Rogue Access Points

2012-10-16 Thread David Cantrell
On Mon, Oct 15, 2012 at 09:00:56AM -0700, Joe Hamelin wrote:
 On Mon, Oct 15, 2012 at 8:54 AM, Roy r.engehau...@gmail.com wrote:
  Why not give them wireless Internet access only?  That will keep all the
  smartphone users happy.
 Maybe because he has 130 sites and 130 truck rolls is not cheap.  Also
 company policy says no.

So stick a pre-configured device in the post, with instructions on how
and where to plug it in.

-- 
David Cantrell | top google result for topless karaoke murders

  Cynical is a word used by the naive to describe the experienced.
  George Hills, in uknot



Re: 100.100.0.0/24

2012-10-16 Thread Nick Hilliard
On 16/10/2012 11:37, Lowe, Richard B wrote:
 Kind of like the 192.0.2.1/32 for IPv4, huh?

no - 192.0.2.0/24 is formally TEST-NET-1, documentation and examples,
like 2001:db8::/32.

100::/64 is specifically for discard and analysis style RTBHs.  I.e. for
ipv6, you can now keep your documentation prefixes on your documentation.

Nick

 RFC: 5635
 
 -Original Message-
 From: Nick Hilliard [mailto:n...@foobar.org] 
 Sent: Sunday, October 07, 2012 6:40 AM
 To: nanog@nanog.org
 Subject: Re: 100.100.0.0/24
 
 On 07/10/2012 00:34, Randy Bush wrote:
 ipv6 route 2001:DB8:0:DEAD:BEEF::1/128 Null0
 
 plug: rfc .
 
 100::/64 is reserved for this purpose.
 
 Nick
 
 
 
 




Re: Internet-wide port scans

2012-10-16 Thread Darius Jahandarie
On Tue, Oct 16, 2012 at 12:57 AM, Scott Weeks sur...@mauigateway.com wrote:
 Want to re-write that section or should I respond now?  ;-)

I always thought it wasn't allowed because of 18 USC § 2701, but
IINAL, would be happy to hear otherwise :).

-- 
Darius Jahandarie



Re: Internet-wide port scans

2012-10-16 Thread Valdis . Kletnieks
On Tue, 16 Oct 2012 08:48:47 -0400, Darius Jahandarie said:
 On Tue, Oct 16, 2012 at 12:57 AM, Scott Weeks sur...@mauigateway.com wrote:
  Want to re-write that section or should I respond now?  ;-)

 I always thought it wasn't allowed because of 18 USC  2701, but
 IINAL, would be happy to hear otherwise :)

If a portscan allows access to stored communications, you have bigger
problems.


pgpS7298U95u0.pgp
Description: PGP signature


Re: Internet-wide port scans

2012-10-16 Thread Jay Ashworth
- Original Message -
 From: Scott Weeks sur...@mauigateway.com

 From: Darius Jahandarie djahanda...@gmail.com
 
 Either way, in the US at least, it's not legal to port scan random
 machines on the internet, so this was a rather useless exercise. (And
 --
 
 Want to re-write that section or should I respond now? ;-)

I was gonna say {{citation-needed}}, myself, but yeah: Huh?

Cheers,
-- jra
-- 
Jay R. Ashworth  Baylink   j...@baylink.com
Designer The Things I Think   RFC 2100
Ashworth  Associates http://baylink.pitas.com 2000 Land Rover DII
St Petersburg FL USA   #natog  +1 727 647 1274



Re: Internet-wide port scans

2012-10-16 Thread Darius Jahandarie
On Tue, Oct 16, 2012 at 9:46 AM,  valdis.kletni...@vt.edu wrote:
 On Tue, 16 Oct 2012 08:48:47 -0400, Darius Jahandarie said:
 On Tue, Oct 16, 2012 at 12:57 AM, Scott Weeks sur...@mauigateway.com wrote:
  Want to re-write that section or should I respond now?  ;-)

 I always thought it wasn't allowed because of 18 USC  2701, but
 IINAL, would be happy to hear otherwise :)

 If a portscan allows access to stored communications, you have bigger
 problems.

In particular, my understanding was that since you're sending a SYN,
it could very well initiate access to stored communications (although
that may have not been the intent of the SYN). But maybe I'm wrong --
and even if I'm right, this seems like something that probably
wouldn't hold in court very well anyways.

-- 
Darius Jahandarie



Re: Internet-wide port scans

2012-10-16 Thread Valdis . Kletnieks
On Tue, 16 Oct 2012 11:38:52 -0400, Darius Jahandarie said:

 In particular, my understanding was that since you're sending a SYN,
 it could very well initiate access to stored communications (although

What 18 USC 2701 actually says, courtesy of www.law.cornell.edu:

Offense. - Except as provided in subsection (c) of this section whoever:

(1) intentionally accesses without authorization a facility through which an
electronic communication service is provided; or

(2) intentionally exceeds an authorization to access that facility;

and thereby obtains, alters, or prevents authorized access to a wire or
electronic communication while it is in electronic storage in such system shall
be punished as provided in subsection (b) of this section.

First off, I believe (but don't have citation handy) there's actual case law
that says that a SYN scan doesn't count as access (either without or exceeding
authorization).  And that's *stored* communications (in other words, your
mail spool, not mail in-flight).

You're better off chasing 18 USC 2511 (wiretapping, where the bits are in
motion), and of course the 800 pound gorilla would be 18 USC 1030 (Fraud and
related activity in connection with computers).

And I'm pretty sure that an NMAP scan doesn't rise to the definition of
'accessed' for any of those.  Of course, if the answer actually matters, ask a
competent lawyer you've paid for advice. ;)



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Description: PGP signature


Re: best way to create entropy?

2012-10-16 Thread Aaron Toponce
On Sat, Oct 13, 2012 at 11:11:20PM +0100, Jasper Wallace wrote:
 and with ekeyd-egd-linux you can distribute the entropy from an entropykey 
 over the net - great for giving vm some randomness.

You would then be interested in http://hundun.ae7.st. Server I setup just a
week or so ago doing this very thing. However, if using a server's random
data, it's important you mix it into your /dev/random device, rather than
using the data directly. After all, how can you trust the admin, that he's
not keeping track of which client is receiving which data?

-- 
. o .   o . o   . . o   o . .   . o .
. . o   . o o   o . o   . o o   . . o
o o o   . o .   . o o   o o .   o o o


pgp1DdYvJwhzK.pgp
Description: PGP signature


Re: Detection of Rogue Access Points

2012-10-16 Thread Ryan McBride
On Mon, Oct 15, 2012 at 04:31:34PM -0700, Joe Hamelin wrote:
 I think it would be cheaper to have a script written that would grab the
 ARP table of each site and then compare to what is known.  Kind of an ARP
 tripwire. 

Netdisco does this, and more (reports on ports which have more than 1
MAC address, devices from known wireless manufacturers, search MAC
address by manufacturer, etc).

http://www.netdisco.org/



Re: Internet-wide port scans

2012-10-16 Thread Jimmy Hess
On 10/16/12, Darius Jahandarie djahanda...@gmail.com wrote:
 On Tue, Oct 16, 2012 at 12:57 AM, Scott Weeks sur...@mauigateway.com
 wrote:
 I always thought it wasn't allowed because of 18 USC § 2701, but
 IINAL, would be happy to hear otherwise :).
18 USC 2701 is not necessarily the only  consideration.

I would rather say that there might be a risk of criminal and civil
liability,  for all entities intentionally participating in, assisting
as accomplices in, or facilitating as service provider, software
provider, providers of information or operating instructions, etc,
for, anyone conducting or intentionally assisting an unauthorized port
scan  of  a different ISP's address space,  that varies with
jurisdiction, and you should consult your counsel,  to determine if
any precautions are appropriate to manage the risk,  such as obtaining
proper  Letters of authorization from IP address assignees in advance,
 or if the responsible entity determines that you must abstain from
the activity entirely, because the risk level is too high.

By definition a  reputable service, will not have a policy that you
may execute internet-wide port scans of arbitrary ports that include
IP networks/addresses that are not either assigned to you, your ISP
customer,  or that you have specific written permission to scan,  as
they will want to manage the risks to themselves properly as well.

Port scans are strongly associated with malicious activity.

And there are other risks of adverse actions, besides legal ones, such
as the service provider's address space becoming widely blacklisted or
becoming depeered.


Before a network service provider offers any kind of service that
permits the SPs' services
to be used for arbitrary port scans of other remote networks, they are
likely to have taken steps to  protect themselves,  by setting some
terms of use and policy restrictions on  what conditions and
parameters must be met, before a scan is allowed.




 Darius Jahandarie
--
-JH



Re: processing passwords?

2012-10-16 Thread Jay Ashworth
- Original Message -
 From: Jean-Pierre A. Radley a...@jpr.com


 | $ JRA=test echo $JRA
 |
 | does not work in the superficially obvious manner, but it makes
 | sense
 | after I think about it -- it's like trying to use sudo with
 | redirection.
 |
 | That behavior is documented back to the v7 shell, I'm pretty sure,
 | though
 | my v7 UPM is at home.
 |
 
 Your shell isn't behaving like mine, in that case. I start out in tcsh
 and:
 
 jpradley:appl 6 sh
 $ unset JPR
 $ JPR=test echo $JPR
 
 $ echo $JPR
 test

tcsh, not especially to my surprise, does not meet the SVID or POSIX, then.

_Unix Shell Programming_, Kochan and Wood, 1985, Hayden, p 251:

Another Way To Pass Variables To A Subshell

If you want to send the value of a variable to a subshell, there's another
way to do it besides setting the variable and then exporting it.  On the
command line, you can precede the name of the command with the assignment 
of as many variables as you want.  For example:

  DBHOME=/unx2/data DBID=452 dbrun

places the variables DBHOME and DBID, and their indicated values, into the
environment of dbrun, and then dbrun gets executed.  *These variables will
not be known to the current shell; they're created only for the execution 
of dbrun.*

(Emphasis mine).

Cheers,
-- jra
-- 
Jay R. Ashworth  Baylink   j...@baylink.com
Designer The Things I Think   RFC 2100
Ashworth  Associates http://baylink.pitas.com 2000 Land Rover DII
St Petersburg FL USA   #natog  +1 727 647 1274



Re: 14 years ago today....

2012-10-16 Thread Jay Ashworth
- Original Message -
 From: Rodney Joffe rjo...@centergate.com

 ... we lost Jon.
 
 http://www.ietf.org/rfc/rfc2468.txt

Be liberal in what you accept, and conservative in what you send.

I don't remember the timing; did Jon borrow that from Fidonet's 
Be ye not overly annoying, nor too easily annoyed?  Or the other way
'round?

Cheers,
-- jra
-- 
Jay R. Ashworth  Baylink   j...@baylink.com
Designer The Things I Think   RFC 2100
Ashworth  Associates http://baylink.pitas.com 2000 Land Rover DII
St Petersburg FL USA   #natog  +1 727 647 1274



Re: best way to create entropy?

2012-10-16 Thread Jimmy Hess
On 10/16/12, JC Dill jcdill.li...@gmail.com wrote:

It's interesting...  though Lava lamps require heat to work, so not
necessarily energy efficient.   In theory, you shouldn't really need
the lava lamp part.   Just the digital camera  part.. operate at a
high ISO, say ISO 3000, dark background, and manual shutter and
aperature controls,  configured to achieve exposure with minimal light
(E.g. a lowest possible usable exposure at the highest speed you can
get),  analyze, and discard the value of any pixels that statistically
show as hot or correlated and capture the inherent CCD sensor
noise due to unpredictability of electrons,  which you maximized,
without having to have any movement in the scene.

 You might want to take a look at:
 http://www.lavarnd.org/news/lavadiff.html

 jc
--
-JH



Please, talk me down.

2012-10-16 Thread Joseph Anthony Pasquale Holsten
I want to like IPv6. I do. But I'm seriously considering turning off IPv6 
support from our servers.

First off, I'm using djbdns internally and it doesn't support  records. So 
we really aren't using it internally.

But today I noticed that we have a lot of traffic to our DNS cache, and started 
to investigate. Turns out that every DNS request would start with one for the 
 record. Ah, no luck. Maybe you forgot the search domain? Let's retry that 
DNS request with that tacked on. Failed again? Meanwhile, lets simultaneously 
try for the AA record then. Repeat.

I'm _this_ close to turning IPv6 off entirely. Anyone want to talk me off this 
ledge?
--
http://josephholsten.com


Re: Please, talk me down.

2012-10-16 Thread Mikael Abrahamsson

On Wed, 17 Oct 2012, Joseph Anthony Pasquale Holsten wrote:

But today I noticed that we have a lot of traffic to our DNS cache, and 
started to investigate. Turns out that every DNS request would start 
with one for the  record. Ah, no luck. Maybe you forgot the search 
domain? Let's retry that DNS request with that tacked on. Failed again? 
Meanwhile, lets simultaneously try for the AA record then. Repeat.


You're describing normal behaviour. Why do you feel the behaviour you're 
seeing is a problem? Because you're not running IPv6, you're seeing twice 
the DNS traffic in some cases.


Doing multiple lookups for everything in search domain is done for IPv4 as 
well.


--
Mikael Abrahamssonemail: swm...@swm.pp.se



Re: Please, talk me down.

2012-10-16 Thread Mike Lyon
Upgrade djbdns to support IPV6? Think there is a patch for it...

-mike

Sent from my iPhone

On Oct 16, 2012, at 20:36, Joseph Anthony Pasquale Holsten
jos...@josephholsten.com wrote:

 I want to like IPv6. I do. But I'm seriously considering turning off IPv6 
 support from our servers.

 First off, I'm using djbdns internally and it doesn't support  records. 
 So we really aren't using it internally.

 But today I noticed that we have a lot of traffic to our DNS cache, and 
 started to investigate. Turns out that every DNS request would start with one 
 for the  record. Ah, no luck. Maybe you forgot the search domain? Let's 
 retry that DNS request with that tacked on. Failed again? Meanwhile, lets 
 simultaneously try for the AA record then. Repeat.

 I'm _this_ close to turning IPv6 off entirely. Anyone want to talk me off 
 this ledge?
 --
 http://josephholsten.com



Re: Please, talk me down.

2012-10-16 Thread Jima

On 2012-10-16 21:35, Joseph Anthony Pasquale Holsten wrote:

I want to like IPv6. I do. But I'm seriously considering turning off IPv6 
support from our servers.

First off, I'm using djbdns internally and it doesn't support  records. So 
we really aren't using it internally.


 It sounds like this is a djbdns problem, not an IPv6 problem.

 FWIW, DJB's public take on IPv6 can be found here: 
http://cr.yp.to/djbdns/ipv6mess.html .  Judging by the lack of updates 
in the past 10 years (OK, 10 years next month), I'm not certain whether 
his position has changed.  (Granted, some of the ten-year-old facts 
have, so who knows.)  Personally, I didn't agree with his perspective at 
the time, and I feel it's only gotten less valid over time.



But today I noticed that we have a lot of traffic to our DNS cache, and started 
to investigate. Turns out that every DNS request would start with one for the 
 record. Ah, no luck. Maybe you forgot the search domain? Let's retry that 
DNS request with that tacked on. Failed again? Meanwhile, lets simultaneously 
try for the AA record then. Repeat.


 Are 2x the queries -- in exchange for future-proofing the network -- 
coming that close to overloading your DNS cache?  You may want to 
re-evaluate the scalability of your cache.


 Or replace your DNS cache with something maintained in the last decade 
(I thought I was exaggerating, but the last changelog in 1.05 is 
20010211), and deploy all your internal assets on IPv6 -- thus reducing 
the query load AND getting your systems ready for the future.



I'm _this_ close to turning IPv6 off entirely. Anyone want to talk me off this 
ledge?


 Go right ahead.  But first, what company is this, so the rest of us 
can know to avoid doing business? ;-)


 Jima




Re: Please, talk me down.

2012-10-16 Thread Randy Bush
 First off, I'm using djbdns internally and it doesn't support 
 records. So we really aren't using it internally.

if the clutch in my car is broken, should i stop using vehicles?

dump djbdns or get some diehard to tell you how to fix it.

randy



Re: Detection of Rogue Access Points

2012-10-16 Thread Jimmy Hess
On 10/14/12, Karl Auer ka...@biplane.com.au wrote:
 No-one has said this yet, so I will - why are people working around your
 normal network policies? This is often a sign of something lacking that
 people need in their daily work. You can often reduce this sort of
While that's no reason to stop looking for rogues...
It's a good point that policy and planning there is a crucial element;
 more important than managing all network devices;  or even having
antivirus or firewalls.

Because humans are a weak point --  every enterprise has them: there
are   ways the humans can be exploited unwittingly,  humans might
sometimes follow an improper procedure,the eventual occurrence of
an incident related to human weakness may be inevitable.

Lacking something they need is not likely.  If it's really true that a
forbidden thing is needed for their work -- they should be able
to persuade   their org's leadership to create a variance from the policy,
or implement a solution.

It's more likely the network user introduces rogue devices because

(1) The rule wasn't written down..   E.g.  It was actually an
unwritten policy never carefully formulated into writing, that nobody
may just plug in whatever network device wireless AP, 5 port switch,
or Linksys router, even with a good reason to;  the network users
had no document to follow to explain  mandatory steps required to
introduce a new device.

(2) The people don't know what the policy, standard, or directive
actually is: They haven't been administered adequate training and been
quizzed appropriately on the  relevant policies, standards, and
guidelines;  their role with regard to the policy is not understood
properly.

(3) The organization hadn't made  commitment to the pertinent IT policy clear.

For example:  The network user do not have high certainty that audit
controls and procedures will be in place will detect their infraction
and remove unauth'd equipment. If they are made certain a
violation will be detected, and receive investigation,  the rate of
non-compliance  could be expected to decrease.


 Sometimes it's cheaper to give people what they want than to prevent
 them taking it. Maybe at least consider that as an option.

That depends on what 'they want';  and what regulations apply to the
organization.
The feds may force various organizations into saying no,  even if
network users want
it, and the org. would prefer to allow it.


If what the network users want is an  unmanaged personal device on a
corporate intranet,
there are security considerations,   which have a non-zero level of
risk, that might be judged too high.

Bandwidth and   potentially firewall user  licenses  for i-devices  to
have continuous Facebook   and Youtube access are not free.

The possibility of required incident management for potential abuse cases.
Possible SOX requirements  to archive  Twitter/Facebook   status
update message traffic

etc. etc.



 Regards, K.
 Karl Auer (ka...@biplane.com.au)
--
-JH



Re: Please, talk me down.

2012-10-16 Thread Karl Auer
On Tue, 2012-10-16 at 21:59 -0600, Jima wrote:
   FWIW, DJB's public take on IPv6 can be found here: 
 http://cr.yp.to/djbdns/ipv6mess.html .

After a quick read, it seems that that statement completely fails to
consider dual stack as a transition mechanism.

Regards, K.

-- 
~~~
Karl Auer (ka...@biplane.com.au)
http://www.biplane.com.au/kauer
http://www.biplane.com.au/blog

GPG fingerprint: AE1D 4868 6420 AD9A A698 5251 1699 7B78 4EEE 6017
Old fingerprint: DA41 51B1 1481 16E1 F7E2 B2E9 3007 14ED 5736 F687




Re: Please, talk me down.

2012-10-16 Thread Mark Andrews

In message 2801f5f8-b8e2-4a9f-9a89-02d7783cc...@josephholsten.com, Joseph Ant
hony Pasquale Holsten writes:
 I want to like IPv6. I do. But I'm seriously considering turning off
 IPv6 support from our servers.
 
 First off, I'm using djbdns internally and it doesn't support 
 records. So we really aren't using it internally.

djbdns doesn't support lots of things.
 
 But today I noticed that we have a lot of traffic to our DNS cache, and
 started to investigate. Turns out that every DNS request would start
 with one for the  record. Ah, no luck. Maybe you forgot the search
 domain? Let's retry that DNS request with that tacked on. Failed again?
 Meanwhile, lets simultaneously try for the AA record then. Repeat.

It looks like your getaddrinfo implementation is a searching for
 records and then searching for A records.  With a A record for
name2 you get a query path like this.

e.g.name1   - NXDOMAIN
name2   - NODATA
name3   - NXDOMAIN
name1 A - NXDOMAIN
name2 A - DATA

You could ask you vendor to implement a alternating search strategy.

e.g.name1   - NXDOMAIN
name1 A - NXDOMAIN
name2   - NODATA
name2 A - DATA

Additionally you could get your vendor skip the A lookup on NXDOMAIN
from .

e.g.name1   - NXDOMAIN
name2   - NODATA
name2 A - DATA

 I'm _this_ close to turning IPv6 off entirely. Anyone want to talk me
 off this ledge?
 --
 http://josephholsten.com
 
-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742 INTERNET: ma...@isc.org



Re: Please, talk me down.

2012-10-16 Thread Octavio Alvarez


On Tue, 16 Oct 2012 20:35:11 -0700, Joseph Anthony Pasquale Holsten  
jos...@josephholsten.com wrote:


I want to like IPv6. I do. But I'm seriously considering turning off  
IPv6 support from our servers.


First off, I'm using djbdns internally and it doesn't support   
records. So we really aren't using it internally.


But today I noticed that we have a lot of traffic to our DNS cache, and  
started to investigate. Turns out that every DNS request would start  
with one for the  record. Ah, no luck. Maybe you forgot the search  
domain? Let's retry that DNS request with that tacked on. Failed again?  
Meanwhile, lets simultaneously try for the AA record then. Repeat.


I'm _this_ close to turning IPv6 off entirely. Anyone want to talk me  
off this ledge?


You will eventually have to turn it on again, so you may run away from
the problem that will catch you up anyway or, better, start tackling
the problems, like fixing djbdns or replacing it with something that
works.

That's my way of seeing it. Good luck with it.


--
Octavio.

Twitter: @alvarezp2000 -- Identi.ca: @alvarezp



Re: Please, talk me down.

2012-10-16 Thread Antonio Querubin

On Wed, 17 Oct 2012, Joseph Anthony Pasquale Holsten wrote:

First off, I'm using djbdns internally and it doesn't support  
records. So we really aren't using it internally.


Sounds like a self-inflicted wound.  You have alternatives.

I'm _this_ close to turning IPv6 off entirely. Anyone want to talk me 
off this ledge? -- http://josephholsten.com


You can stay on the ledge if you like.  A lot of folks have already 
decided to move on...


Antonio Querubin
e-mail:  t...@lavanauts.org
xmpp:  antonioqueru...@gmail.com



Re: Please, talk me down.

2012-10-16 Thread JP Viljoen
On 17 Oct 2012, at 5:35 AM, Joseph Anthony Pasquale Holsten 
jos...@josephholsten.com wrote:
 I want to like IPv6. I do. But I'm seriously considering turning off IPv6 
 support from our servers.
 
 First off, I'm using djbdns internally and it doesn't support  records. 
 So we really aren't using it internally.
 
 But today I noticed that we have a lot of traffic to our DNS cache, and 
 started to investigate. Turns out that every DNS request would start with one 
 for the  record. Ah, no luck. Maybe you forgot the search domain? Let's 
 retry that DNS request with that tacked on. Failed again? Meanwhile, lets 
 simultaneously try for the AA record then. Repeat.

++ on what everyone else has said about this being a problem with the way you 
run your DNS infrastructure, instead of an actual IPv6 problem.

Without reasons listed for why you use djbdns, I can't really adequately 
comment, but: on our net we're using unbound as caching DNS servers with pretty 
good success, and pdns with dynamic backends (the backends are custom in-house 
stuff) as our authoritative DNS. Short of issues now and then with the 
backends, it works pretty well.

-J