Windows Win7 64bit premium - DNS messing up :(

Hi all,

Before I explain the problem let me given the setup, I have a standard spec machine on a network with several others, I have just upgraded it to win7 64bit from vista 32bit, On the network is a web server which is also our dns server. Everyone can resolve this domain and all subdomains (including my old installation of vista) without any slowdowns or other issues.

We have 1 internal domain (example.com) and for every website we make we create subdomain on that server i.e. (website1.example.com).

The problem is that my machine seems unable to consistently resolve either externally or internally, I can't seem to get both permenantly working whilst the other is.

I have tried setting my DNS servers manually i.e. dns1 is my internal IP and dns2 is an external dns server, this setup works fine on the Macs in the building. I have also tried "Auto" which works fine on the Vista machines.

If I set it to Auto, internal domains will resolve for a short while and then server will be unresolvable although external domains will continue to work. If I use the 2 dns servers manually it will work a little longer, but the local domains will soon become unresolveable (10mins or so)

I have also tried only specifying 1 dns server (the internal one) and that means all internal domains will work, but after a short while the external websites will stop working.

I have checked my HOSTS file and there is nothing in there that shouldn't be, I have also tried forcing the local IP for the local domain and this seems to work, but I can't do this for every subdomain (there are 100's) can I use wildcards i.e. *.example.com in my HOSTS file?

Or perhaps there is another solution or a 'feature' in windows 7 which needs turning off?

Andy

 

shouldn't have to.. I still run vista- probably a win 7 thing, you check services and make sure the DHCP Client is running.. you could try disabling the DNS Client temporary and see if it's a cache issue

make sure network discovery is on http://windows.microsoft.com/en-US/windows7/What-is-network-discovery

 

A silly question? Your machine is joined to the Windows domain right? If not, was the Vista machine? But assuming everything is part of the domain...

Okay, looks like you need to find out what DNS server settings your machine is getting when over DHCP.

An "IPConfig /all" will do that from a command prompt.

And then you can test these specifically with your internal / external lookups. Use nslookup from a command prompt to do this, it's really useful to be able to manually query each DNS server from the client machines and ask it to resolve specific IPS. Google it and play with it if not familiar.

You could also try this...

Manually set your two DNS servers the 1st to your internal DNS server, and the second to a working publoc DNS (Google @ 8.8.8.8 is good)

But...

I would suggest you get your sys-admin (you?) to look at the DNS settings on your internal DNS server. My guess is it's not resolving non authorisative queries, there's a setting in there someone depending on your config.

Good luck.

PS. You can also use an "ipconfig /flushdns" when testing to imediately force the forgetting of DNS lookups and cure the "it stops working after 10 mins" issues. If you fully flush your DNS then you'll see immediately if there is a problem.

If all else fails...

Set your DNS to a working external server (EG google)

And manage everything else via your hosts file, a pain if you have lods of dynamic IPs but otherwise OK (ish)

 

Hey guys,

I've done everything except checked the DHCP server, where can I check if its enabled? In ipconfig /all it says it isn't enabled there?

Any ideas appreciated. dns flush and disabling/enabling DNS didn't work either.

Andy

 

check to make sure the nic is compatible.. probably a driver issue.. it's not a cache issue and the other rigs can see the servers

what do you get with nslookup or pinging the dns server

http://www.microsoft.com/windows/compatibility/windows-7/en-us/Search.aspx

 

If I ping the dns server whilst I can still view the pages it works fine, afterwards no connection, same for external. Apparently NIC is compatible and drivers are up-to-date.

What is nslookup (sorry for the n00b question).

Thanks for the help so far, really want to solve this! Am having to open up network settings every so often to either view external or internal domains. Frustrating to say the least!

If having a hosts file entry fixes the problem does this suggest something's wrong with my machines DNS settings when trying to connect to local domains? As when my DNS settings are on auto I get external DNS working fine, and internal DNS will break after a short while.

I also checked this: http://windows.microsoft.com/en-US/windows7/What-is-network-discovery and its turned on.

Thanks again for your help!

 

nslookup - allows you to perform lookups against you're "name server" n-s-lookup. Your name server in this instance is your DNS server, the server your PC asks the question "What is the IP for the URL www.wibble.com"

You run nslookup from a command prompt, type in this:

server x.x.x.x

replacing x.x.x.x with the IP of the server you wish to test.

Then you type in the URL / name you want to test, EG:

www.wibble.com

or

mynetworkpcname

You can then tell if the DNS server you are using is able to "resolve" the address / name it's being asked for.

 

Hi thanks for the advice, I however get this:

Code:

'server' is not recognized as an internal or external command,
operable program or batch file.

when I type this:

Code:

server 192.168.1.2

Any advice regarding this, I am using command prompt to run it, start->run "cmd". Is this correct?

 

You have to start nslookup first

1. Open a command prompt
2. Type nslookup
3. Type server x.x.x.x (replace as appropriate)
4. Type url / name to lookup eg www.bit-tech.net
5. See the result

You should get spec on the type of answer, the name you looked up and the IP address. EG for www.bit-tech.net I get:

Non-authoritive answer:
Name: www.bit-tech.net
Address: 91.198.165.67

I'm using the new google DNS severs they made public a few weeks back so my default DNS server is 8.8.8.8.

That's all I've ever used nslookup for, if you want learn more, then google will be your web-buddy

 

C:\Users\Andy>nslookup
DNS request timed out.
timeout was 2 seconds.
Default Server: UnKnown
Address: 192.168.1.2

> server www.bit-tech.net
DNS request timed out.
timeout was 2 seconds.
DNS request timed out.
timeout was 2 seconds.
DNS request timed out.
timeout was 2 seconds.
Default Server: www.bit-tech.net
Address: 91.198.165.67

This is what I get when my primary DNS server is set to our internal one 192.168.1.2 and secondary is to 8.8.8.8

Any ideas?

 

I see two issues:

Your default DNS server (192.168.1.2) is timing out

You typed "server www.bit-tech.net", which means you're telling ns lookup to peform lookups on the DNS server called "www.bit-tech.net" - which there isn't one.

Type:

nslookup
www.bit-tech.net
server 8.8.8.8
www.bit-tech.net

That will perform one lookup using your default DNS (192.168.1.2)
And a second on the google DNS (8.8.8.8)

See if there is a difference.

 

To be really sure you're testing both server, type:

nslookup
server 192.168.1.2
www.bit-tech.net
server 8.8.8.8
www.bit-tech.net

 

Code:

C:\Users\Andy>nslookup
DNS request timed out.
    timeout was 2 seconds.
Default Server:  UnKnown
Address:  192.168.1.2

> server 192.168.1.2
Default Server:  [192.168.1.2]
Address:  192.168.1.2

> www.bit-tech.net
Server:  [192.168.1.2]
Address:  192.168.1.2

DNS request timed out.
    timeout was 2 seconds.
DNS request timed out.
    timeout was 2 seconds.
DNS request timed out.
    timeout was 2 seconds.
DNS request timed out.
    timeout was 2 seconds.
*** Request to [192.168.1.2] timed-out
> server 8.8.8.8
DNS request timed out.
    timeout was 2 seconds.
Default Server:  [8.8.8.8]
Address:  8.8.8.8

> www.bit-tech.net
Server:  [8.8.8.8]
Address:  8.8.8.8

Non-authoritative answer:
Name:    www.bit-tech.net
Address:  91.198.165.67

>

Looks like external DNS just isn't working on the local IP, but surely if I supply a secondary dns server in settings then if the first fails it uses the second? or does windows require the server to say it doesn't know?

Thanks for the amazing help so far!

 

So using Google's DNS server, you can resolve external addresses?
Can you resolve internal hostnames using your internal DNS server?

 

Yeah, and yeah!

What am I doing wrong? haha!

 

Anyone know the problem with this setup? :-(

 

Well it looks like your local DNS server is not passing requests for external sites to DNS servers on the internet.
My experience of this is zero though, so I'm not sure how to fix - is your DNS server set to use the correct external DNS addresses?

 

Yeah, thats the weird thing. It works on all other machines (this is the only windows 7 machine in the building) and this machine worked fine when it was windows vista. oddbox!

 

might want to wade through this thread.. maybe someone with a similar config in there

http://social.answers.microsoft.com...k/thread/0014801b-7e82-4bb6-a8e7-e8867eb3fcee

 

There's definately a setting in the windows DNS server settings, but it's a few years since I've managed such a config, so can't say what you need to do to the server to get the issue resolved.

My gut feeling is ms have "fixed" something in win7, which wasn't quite right before. All your other machines are using a "broken" os and therefore doing some extra routing or similar.