Re: unable to join domain from DMZ

[Charles Otstot <charles.otstot () ncmail net>]

Erich D. Heintz wrote:



> > > > I think the point of using an LMHOSTS file in this case over WINS is th=
> >    
at

> > > > the system at issue is in a DMZ.
> > > >
> > > > There's been nothing stated as to whether or not WINS exists in the LAN=
> >    

> > > > segment and it's really not relevant unless you plan to open conduits t=
> >    
o

> > > > allow WINS to work between the DMZ and the LAN.
> > > >
> > > > An LMHOSTS entry is the best option here, IMHO, since it provides the
> > > > minimum amount of information needed by the DMZ system to be functional=
> >    
=2E

> > > > Putting a WINS server in the DMZ or allowing WINS traffic to traverse
> > > > between the LAN and the DMZ simply makes more information about the LAN=
> >    

> > > > available to the DMZ than is needed.
> > > >
> > > > =20
> >    
> >
> > =20
>  
<snip to end>

At this point, we really don't have enough information to determine wheth=
er LMHOSTS *is* the way to go (as you noted, no information has been give=
n regarding the status of WINS on the LAN,although it would be highly unl=
ikely that an NT 4.0 domain  of any size would function reasonably withou=
t it). At first glance, it appears that a LMHOSTS file may be the best wa=
y, however, there are a number of other factors that could affect the app=
ropriateness of such a decision. How many internal hosts reauire communic=
ation with this server? What do they do(e.g. monitoring hosts, SUS or SMS=
servers, etc.)? Are there any plans afoot that may alter the IP addresse=
s of a significant number of those hosts? How many domains does the serve=
r need to communicate with? Are there any functions resident on this host=
that require the ability to validate against more than it's parent domai=
n (Hopefully not, but it is possible)?

*Assuming* only domain validation is required and further assuming that t=
here are only a limited number of domain controllers with which the DMZ h=
ost needs to communicate, then LMHOSTS is likely the proper solution. Oth=
erwise, the benefits of limited communication may outweigh the costs (e.g=
=2E extra monitoring hosts, additional administrative time requirements, =
etc.) of either installing WINS or opening the firewall to WINS traffic. =
Maintaining LMHOSTS in a large, fluid environment can be cumbersome and e=
asily lead to easily mis-diagnosed communication problems(it's easy to fo=
rget that a given host uses LMHOSTS rather than WINS and look elsewhere f=
or the source) if (more often *when*) a required host moves between segme=
nts and requires a new IP address.
Based on what has been posted, only the original poster has enough inform=
ation to adequately analyze the options available.

At this point I wouldn't be comfortable recommending either WINS or LMHOS=
TS as the *right* solution. I will offer a link that may be helpful. In t=
he event the original poster decides to go with LMHOSTS, here is a link t=
o Microsoft's KB article for creating an LMHOSTS file for Domain Validati=
on:

http://support.microsoft.com/default.aspx?scid=3Dkb;EN-US;180094


Charlie



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