really odd DNS issue

B

big daddy fatsacks

2[H]4U
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Aug 10, 2001
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so i'm trying to help my brother get his network at work running properly, and there's this wierd DNS problem that i can't figure out. he has all windows server 2003 servers including 2 AD-integrated DNS servers. when he runs nslookup on ANY box in the domain he'll get

Code: 
> [url]www.2cpu.com[/url]
Server:  fsmo.domain.com
Address:  10.0.0.106

Non-authoritative answer:
Name:    2cpu.domain.com
Address:  205.177.13.40
Aliases:  [url]www.2cpu.com[/url]

i cannot figure out why DNS is appending his domain name to every query. anyone care to venture a guess?
 
Is there a DNS suffix supplied for the machine? My understanding is this will apply that suffix to every connection

For example if the dns suffix supplied is mydomain.com, ping mypc will return mypc.mydomain.com. Its in your advanced TCP/IP settings on the DNS tab.

 
i tried changing that right off the bat, but it didn't fix the problem. i may get back on and retry it since it was late and i may not have gone through with it correctly.

Party2go9820 said:
Is there a DNS suffix supplied for the machine? My understanding is this will apply that suffix to every connection

For example if the dns suffix supplied is mydomain.com, ping mypc will return mypc.mydomain.com. Its in your advanced TCP/IP settings on the DNS tab.

Click to expand...
 
I know with win2k, I was advised to delete the default <.> zone... could this be the problem??

QJ
 
You don't need to make any changes to the TCP/IP config>>DNS suffix list. dns suffixes only affect the search order.

Ie: if you have a default domain name (domain.com) and a few other domain names in the suffix list (domain2.com, dom3.com)... Then when you do a lookup with no FQDN it will then use those as a search path.

Ie: "nslookup hostX" will return the first response that comes up with "hostX.<domain>" In other words, if domain.com and domain2.com do not have an A record or CNAME entry for "hostX" and dom3.com does.. Then it will respond with the corresponding A/CNAME for "hostX.dom3.com". Sorry to go off on the tangent, but I just wanted to clarify that a little.
_________________________
Now, I'm not really an AD guru. But I'm guessing that there's some sort of DNS masquerading going on.

I'd go into your DNS Server settings and make sure there's no "masq" option enabled. Also try checking to see if there's a catch-all. Do a host lookup on a non-existant domain like "www.asdfkjadkljasdf.com" or something and make sure it returns NXDOMAIN. Then look up a non-existant host record.

I'm pretty sure it's some goofy check-box left on that shouldn't be in M$ DNS Server Administrator.

(Gotta lurve BIND.)
 
i talked to my brother today and told him to post here with more info if none of the suggested checks resolves the problem.
 
some I'm the brother with the broken DNS. I looked into the above suggestions and nothing made a difference.

Basically when I query dns from any computer on the domain it appends .mydomain.com to the end of whatever I put there. mydomain.com is also a public domain so it resolves to an address since there is a public DNS record for *.mydomain.com

When I do: nslookup www.microsoft.com dc1 (dc1 being my primary dns controller) it returns:

Server: dc1.global.mydomain.com
Address: XXX.XXX.X.X

Non-authoritative answer:
Name: www.microsoft.com.mydomain.com
Address: XX.XXX.XX.XXX (the public IP address that *.mydomain.com points to)

But when I do: nslookup www.microsoft.com. dc1 (the important difference being the DOT after com)

it returns:

Server: dc1.global.mydomain.com
Address: XXX.XXX.X.X

Non-authoritative answer:
Name: www.microsoft.com.nsatc.net
Address: 207.46.18.30
Aliases: www.microsoft.com

I've tried I don't know how many different things as has my brother so at this point I'm fishing, I'll try anything. I've already rebuilt the dns on each DC from scratch and still have the same problem.

Another thing of note is when I run those above nslookups but specify my ISP's DNS servers it will still append something to the end but this time it appends global.mydomain.com which is the entire name of my internal domain whereas when I query directly to my internal DNS servers it only appends mydomain.com.

I'm about to go insane at this point. Any help would be appreciated.
 
I'm not a windows guru, but if this was on linux I would say you missed a period. In bind you have to put a . at the end of the addresses or else it will append the domain twice.

For instance for a machine with the name dns.domain.com you need to put in:
dns.domain.com. IN A IP_ADDRESS

Is there a chance something like this is needed in you Windows setup?
 
you mean for each A record? or just for like the SOA or NS recs? in ny case i'll check my boxen out to see how it is and compare. thanks for the suggestion.
deuce868 said:
I'm not a windows guru, but if this was on linux I would say you missed a period. In bind you have to put a . at the end of the addresses or else it will append the domain twice.

For instance for a machine with the name dns.domain.com you need to put in:
dns.domain.com. IN A IP_ADDRESS

Is there a chance something like this is needed in you Windows setup?
Click to expand...
 
no missing period anywhere. it's only that when he adds the period to the end of his nslookup it returns the correct answer.

here's something: nslookup is ONLY appending the parent domain suffix, but is leaving off his domain suffix. so he is in global.mydomain.com but his queries return just the microsoft.mydomain.com. the global is left out.

also, the global.mydomain.com domain is the only one in AD. there is no mydomain.com domain above them. that is only used for external services like their web site and such.
 
okay, as soon as i wrote that last post i realized, "hey, global is not being appended. we have that domain setup and DNS running for it. mydomain.com recs are hosted externally, but i wonder how that works since technically this internal domain is a subdomain?" so i created a zone in this DNS server for the mydomain.com parent domain and BOOYAH! seems to work now.

thanks to everyone for the help. working it out aloud really helps.
 
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