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Nick,

 

Thanks for the help, but I have 2 DNS servers installed currently. It has to
be some type of configuration error on my part. I'll keep digging.

 



 

From: Kwiatkowski, Nicholas [mailto:[log in to unmask]] 
Sent: Friday, September 28, 2012 1:16 PM
To: Tim Heckaman; [log in to unmask]
Subject: RE: [MSUNAG] DNS Help

 

The issue stems on what happens when your in-house DNS server fails.

 

If you have the 1st DNS as your AD server, and the 2nd as one of the many
Campus DNS servers, things will go like this :

-          Normally, you will resolve to your AD server.  This is required
to allow people to login, map drives, access AD resources for
authentication, etc.  Requests for regular internet sites (or MSU sites, for
that matter), are handled by your AD server, and if it is not already in its
cache, it will proxy the request to other DNS servers.  

-          If you AD server is unavailable, requests will be handled by
MSU's DNS servers.  This is not a problem, but MSU's DNS servers will have
no idea about your AD servers, printers, file shares, etc.  This will cause
some weird issues, but users will still be able to facebook.

-          If your AD server is slower at responding to DNS than the magic
threshold (I believe in Windows XP, this is a 2,000ms timer), the request
will be asked of the 2nd DNS servers on the list.  Users will still be able
to facebook (as both servers know how to handle these requests), but
sporadically users will not be able to map drives, authenticate, or their
machines will display weird profile errors when booting.  

 

The trick is that MS-AD's DNS service adds all sorts of special tags and
subdomains  to their DNS responses so that Windows machines know how to get
to certain resources.  This was done during the migration from NetBios (and
NetPipes) to IP for address resolution.  If you look at your local AD
server, you will see these entries.

 

Microsoft's recommendation is to have a secondary DNS server setup to help
fulfill these requests when the primary is unavailable, or too slow to
answer the requests.  You would need a secondary Windows box, install DNS
services, and make it a slave of your primary.  This way additions are
automatically propagated to this second server.  

 

-Nick

 

From: Tim Heckaman [mailto:[log in to unmask]] 
Sent: Friday, September 28, 2012 11:41 AM
To: [log in to unmask]
Subject: [MSUNAG] DNS Help

 

I'm sure this is an easy answer but it has got me stumped. I'm running 2
DC's with DNS. I have 1 nic on each machine. In the DNS fields of those nics
I have the primary DC as the first IP to go to to resolve IPs. In the second
I've tried leaving it empty (obviously not correct) and I've tried using the
MSU IP's listed in the network values on
http://network.msu.edu/netinfo/netvalues.html  When I run a "Scan This Role"
I get errors that say "DNS: The DNS server (IP address) on Local Area
Connection must resolve Global Catalog resource records for the domain
controller" and a slew of other errors. I'm also getting warnings that say
"DNS: Root hint server (IP address) must respond to NS queries for the root
zone.

Obviously I'm not a DNS guy but I've tried everything I know to do, and a
ton of research and I'm no closer to getting this issue resolved. Everyone
still has internet access, including my servers but I don't like having
warnings and errors in my logs. If there is a DNS guru out there that would
like to help a noob out please let me know.

 

Thanks