Cloudflare reverse DNS SERVFAIL, normal?

Owen DeLong owen at delong.com
Tue Aug 30 23:41:25 UTC 2016


> On Aug 30, 2016, at 15:02 , Mark Andrews <marka at isc.org> wrote:
> 
> 
> In message <926F8B85-8864-4424-BEAA-1836B718A9FD at delong.com <mailto:926F8B85-8864-4424-BEAA-1836B718A9FD at delong.com>>, Owen DeLong writes:
>>> On Aug 29, 2016, at 17:01 , Mark Andrews <marka at isc.org> wrote:
>>> 
>>> 
>>> In message <20160829234737.GA16137 at cmadams.net>, Chris Adams writes:
>>>> Once upon a time, Mark Andrews <marka at isc.org> said:
>>>>> The following is general and is not directed at Cloudflare.  I know
>>>>> some people don't think errors in the reverse DNS are not critical
>>>>> but if you are delegated a zone it is your responsablity to ensure
>>>>> your servers are correctly serving that zone regardless of where
>>>>> it is in the DNS heirarchy.  Failure to do that causes additional
>>>>> work for recursive servers.  If you don't want to serve a zone then
>>>>> remove the delegation.
>>>> 
>>>> You are assuming that an authoritative server operator has some way to
>>>> know all the zones people delegate to their servers, and remove such
>>>> delegations if they don't want to handle them.  That is a wrong
>>>> assumption.
>>> 
>>> They have methods.  They choose not to use them.  See RFC 1033
>>> COMPLAINTS then after that the court system.
>>> 
>>> Mark
>> 
>> Let us review this and compare to your statement…
>> 
>> From RFC 1033:
>>> COMPLAINTS
>>> 
>>>   These are the suggested steps you should take if you are having
>>>   problems that you believe are caused by someone else's name server:
>>> 
>>> 
>>>   1.  Complain privately to the responsible person for the domain.  You
>>>   can find their mailing address in the SOA record for the domain.
>>> 
>>>   2.  Complain publicly to the responsible person for the domain.
>>> 
>>>   3.  Ask the NIC for the administrative person responsible for the
>>>   domain.  Complain.  You can also find domain contacts on the NIC in
>>>   the file NETINFO:DOMAIN-CONTACTS.TXT
>>> 
>>>   4.  Complain to the parent domain authorities.
>>> 
>>>   5.  Ask the parent authorities to excommunicate the domain.
>> 
>> 1.	Doesn’t really apply in a situation where someone has pointed
>> 	an NS record for a domain at your server without warning. There
>> 	is no SOA record from which to retrieve said mailing address.
> 
> If they have pointed a NS record at you there is a SOA record.  Either
> in the zone or in the delegating zone.

Sure, but most likely this isn’t particularly useful… See below.

> 
>> 	Also doesn’t work very well in cases where the SOA record does
>> 	not contain a valid email address that reaches someone.
> 
> Some do, some don't.  There is also whois address, web contact addresses
> etc.

Sometimes, if you’re lucky, if it all works as intended and the person isn’t
using domain privacy…

> 
>> 2.	Do we really want NANOG buried in “Will the
>> 	@#@[email protected][email protected]$% who delegated XYZ.COM <http://xyz.com/> <http://xyz.com/ <http://xyz.com/>> NS Records to
>> point to
>> 	my servers <name> and <name> please cease and desist?”
>> 	messages? Personally, I vote no.
> 
> Why not.  It is a operational message about a misconfiguration.

Because NANOG isn’t for solving individual misconfigurations. It’s for
discussing issues on the internet requiring coordination.

This doesn’t require coordination of multiple providers, it’s a simple
bug report.

It would significantly raise the N in SNR IMHO. Your opinion may differ.

I still vote no.

> 
>> 3.	The NIC? Please explicate Mr. Andrews what that would mean
>> 	in the modern era. Please cover both the normal case and
>> 	the cases where domain privacy is configured.
>> 
>> 4.	This might _MIGHT_ actually work, but I suspect that $REGISTRY
>> 	is unlikely to help much when $REGISTRAR accepted an NS record
>> 	from one of their customers for a domain they registered
>> 	that happens to point to your server. Similarly, I suspect
>> 	$REGISTRAR is going to tell you that they won’t make changes
>> 	without authorization from the domain owner.
> 
> The registrar becomes party to the disruption to your services and
> no the contract the registry signed with ICANN does not save them
> from being fined by a court further down the process so they should
> listen as it is their finanical interests to listen.

What disruption? It’s pretty hard to argue that sending back some
SERVFAIL responses as a result of a few errant packets on UDP/53
constitutes a significant disruption to service.

> Criminal law trumps contract law and deliberate disruption to
> services falls under criminal law.  It becomes deliberate once they
> fail to act on the complaint in a timely manner.  Remember we are
> dealing with matters of fact here.  Published NS records and address
> records.

Sure, but to get a DA to prosecute for deliberate disruption, one has
to be able to prove intent. Mere misconfiguration is not intent.
Mere misconfiguration followed by ignoring bug reports becomes a little
more grey, but I bet you’re still not likely to get very far without
a much larger disruption to your service in the form of time spent
than you suffer by simply ignoring it.

> Add to that there are published proceedures that are not being
> followed that they should be aware of.

Published procedures don’t have the force of law. They may help you
to create a presumption of misconduct or negligence, but that’s about
as far as they can go.

>> 5.	I suspect that success in this effort will likely parallel
>> 	the level of success I would expect in step 4.
>> 
>> So, now that we’ve realized that RFC-1033 is utterly useless in this
>> context and badly outdated to boot, let’s review your other suggestion…
> 
> No, it isn't utterly useless.  It also shows you have tried to solve
> the problem in a civil manner if you take it further.

It has a less than 0.001% probability of achieving a useful end result.

I consider that within the realm of “utterly useless”. YMMV.

> 
>> “… after that [sic] the court system.”
>> 
>> [sic] refers to the missing comma.
>> 
>> So let me see if I understand correctly.
>> 
>> I run a pair of nameservers. Let’s call them ns1.company.com
>> <http://ns1.company.com/> and ns2.company.com <http://ns2.company.com/>
>> 
>> Someone registers example.com <http://example.com/> and points NS records
>> in the COM zone at my
>> nameservers.
>> 
>> I’m now supposed to seek judicial relief in order to compel them to stop
>> doing that?
>> 
>> Small claims doesn’t process claims seeking injunctive relief. I suppose
>> I could
>> use a $1,500 or even $5,000 small claims case as a way to get their
>> attention,
>> but that’s kind of an abuse of the process. If I want an injunction, at
>> least
>> in California, I have to go to Superior court.
>> 
>> Now, first, we have to figure out jursidiction. As a general rule,
>> jurisdiction
>> goes to the court which is responsible for the locale in which the event
>> takes
>> place or where the contract was entered into, or the jursidiction set by
>> the
>> contract. In this case, there’s no contract, so we have to look at where
>> the
>> event in question occurred. The problem is that the law hasn’t really
>> caught
>> up with technology in this area and depending on who ends up being parties
>> to the suit, the definition gets pretty murky at best. Is it the primary
>> office of the registry? The registrar? The registrant? The location of the
>> nameserver(s) which are erroneously pointed to? (What if they are anycast
>> all over the world?) The business address of the operator or owner of
>> those
>> nameservers? Where, exactly do we file this suit?
> 
> Your lawyer will work that out.

OK, so let me make sure I’m understanding you correctly.

I’m getting these extra packets I don’t want. They’re probably costing me
less than $1/day, but they’re a bit annoying.

You now want me to go pay someone $300/hour to sort all of this out, probably
against a $5,000 or $10,000 retainer just to start?

Will you be financing any of these operations, or, are you just hoping that
we’re all dumb enough to bankrupt ourselves in the name of clean DNS?

>> The next problem we have is who to sue. Do we sue the domain registrant?
>> The
>> registrar they used to register the domain name? etc.
> 
> Your lawyer will work that out.

See above.

>> Yeah, I don’t think there’s enough possibility of any sort of recovery to
>> make that worth the effort or expense.
> 
> So you decide to not avail yourself of the process available to you.  That
> is not the same thing as saying there is no process.

I never said there was no process. I said that the existing process was useless.

If the procedural argument doesn’t convince you and the economic argument doesn’t
sink in, then, you are entitled to your opinion, but I’m willing to bet that a
much larger fraction of the community believes that there is nothing to be gained
from the process compared to the costs of engaging in it.

Owen





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