Violently agreeing. :D

On Fri, Nov 9, 2012 at 12:23 PM, Michael B. Smith <[email protected]>wrote:

> Then I think we are saying the same thing, just in different ways. :)
>
> -----Original Message-----
> From: Ben Scott [mailto:[email protected]]
> Sent: Thursday, November 8, 2012 1:09 PM
> To: NT System Admin Issues
> Subject: Re: Confused about DNS resolution on a server with 2 NICs on a DMZ
>
> On Thu, Nov 8, 2012 at 10:04 AM, Michael B. Smith <[email protected]>
> wrote:
> > Your statements are true in regards to DNS in the abstract. But as you
> allude to, different adapters may have access to different servers and the
> results you obtain - especially when both adapters point to DNS servers
> that have different answers for queries can be surprising.
>
>   That's what I'm trying to say: There's one DNS namespace/cache.
> Resolver query order may be determined by adapter priority, but the
> answers feed into the same cache.  If you try to treat it as anything
> *other* than a system-wide thing, you get those surprises.
>
>   The fact that people fall into the trap of treating Windows DNS as not
> system-wide, doesn't mean it's not actually system-wide.
>
>   If DNS *wasn't* system-wide, having different resolvers configured on
> different network adapters might be able to work -- you'd be able to
> maintain different, disjoint namespaces simultaneously.  But it doesn't
> work that way, and that's the problem.
>
>   Bad car analogy time: My car has one steering wheel.  More than one
> person can grab the wheel and try to steer at once.  It won't end well,
> because while you can provide multiple inputs, steering is a car-wide thing.
>
>   (As an aside: This isn't a Windows-specific problem, either.  You can
> configure multiple resolvers on *nix or most other OSes, too, and if those
> resolvers have different ideas of what the namespace is, the same problems
> occur.)
>
> -- Ben
>
> > -----Original Message-----
> > From: Ben Scott [mailto:[email protected]]
> > Sent: Thursday, November 8, 2012 8:31 AM
> > To: NT System Admin Issues
> > Subject: Re: Confused about DNS resolution on a server with 2 NICs on
> > a DMZ
> >
> > On Wed, Nov 7, 2012 at 6:49 PM, Michael B. Smith <[email protected]>
> wrote:
> >>>  DNS is not specific to a given network adapter.  It's a system-wide
> thing.
> >>
> >> Your first two sentences are not really true with Windows. It's
> >> complicated. :P
> >
> >   My understanding is that the Windows DNS subsystem has a single
> namespace, shared across the entire system.  If a record is cached by the
> local resolver, that cached record is the same for the entire system.  Is
> that incorrect?
> >
> >   I realize the order in which full-service resolvers are tried is
> driven by network adapter priority.
> >
> >   Assuming my understanding is correct: If it's all one namespace, I
> think it's best to consider it a system-wide thing.  DNS *is* the
> namespace, as far as most things are concerned.  Playing games with the
> resolver order to try and influence that single namespace is a very bad
> idea.
>
> ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ ~ <
> http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/>  ~
>
> ---
> To manage subscriptions click here:
> http://lyris.sunbelt-software.com/read/my_forums/
> or send an email to [email protected]
> with the body: unsubscribe ntsysadmin
>
>
> ~ Finally, powerful endpoint security that ISN'T a resource hog! ~
> ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/>  ~
>
> ---
> To manage subscriptions click here:
> http://lyris.sunbelt-software.com/read/my_forums/
> or send an email to [email protected]
> with the body: unsubscribe ntsysadmin
>
>

~ Finally, powerful endpoint security that ISN'T a resource hog! ~
~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/>  ~

---
To manage subscriptions click here: 
http://lyris.sunbelt-software.com/read/my_forums/
or send an email to [email protected]
with the body: unsubscribe ntsysadmin

Reply via email to