**Have to constantly change DNS to enable our Internet access**

[Dave]

We have a problem with Internet access in our company. The
Internet works fine and then all of a sudden it cannot
connect to any site, when we change the DNS settings it
works again for a while and then it stops a week or so
later and we have to change the settings back to the
original and it works again for another few days until we
have to change it again.

Has anyone experienced this proble or does anyone know a
solution to fix it?

Regards,

Dave

 

[Herb Martin]

We have a problem with Internet access in our company. The
Internet works fine and then all of a sudden it cannot
connect to any site, when we change the DNS settings it
works again for a while and then it stops a week or so
later and we have to change the settings back to the
original and it works again for another few days until we
have to change it again.

What DNS setting are you repeatedly changing?
We would know a lot more about helping you if you gave us
the actual settings, symptoms, and the change you make....

Has anyone experienced this proble or does anyone know a
solution to fix it?

What problem?

Best bet is that you have your CLIENT DNS settings misconfigured
with both an INTERNAL and an EXTERNAL DNS server configured
on the NIC (or NICs) but from the lack of information this is very nearly
a pure guess....

 

[Guest]

-----Original Message-----


What DNS setting are you repeatedly changing?
We would know a lot more about helping you if you gave us
the actual settings, symptoms, and the change you make....


What problem?

Best bet is that you have your CLIENT DNS settings misconfigured
with both an INTERNAL and an EXTERNAL DNS server configured
on the NIC (or NICs) but from the lack of information this is very nearly
a pure guess....

--
Herb Martin


.

What DNS setting are you repeatedly changing?

The DNS in TCPIP settings on the client PC.


symptoms?

Internet works fine and then all of a sudden it cannot
connect to any site, when we change the DNS settings it
works again for a while and then it stops a week or so
later and we have to change the settings back to the
original and it works again for another few days until we
have to change it again.

 

[Herb Martin]

What DNS setting are you repeatedly changing?

The DNS in TCPIP settings on the client PC.


symptoms?

Internet works fine and then all of a sudden it cannot
connect to any site, when we change the DNS settings it
works again for a while and then it stops a week or so
later and we have to change the settings back to the
original and it works again for another few days until we
have to change it again.

You said all that the first time (except for the answer to "what settings"
and even that isn't very specific).

If you expect help you are going to need to be much more specific.
Did you try the suggestion from my first post?

Does this happen on multiple machines or just one client?
Run "IPConfig /all >ipconfig.txt" and post the results here.

Where is your DNS server? What IP? Do you have more than
one?

What SPECIFICALLY do you change on the client when you make
it work?

Before you change it next time, try NSLookup to each of your DNS
servers and see if each and ALL give the same results.

 

[Michael Johnston [MSFT]]

This sounds like a DNS cache problem. When you change the DNS settings, it flushes the current cache and this may be
what's actually fixing this. As a test, the next time this fails run "ipconfig /flushdns" and test connecting to the Internet. If this works,
then it was a caching problem. If it still doesn't work, go to your DNS servers and flush the DNS cache on the DNS servers. If
these are Windows 2000 DNS servers, to flush the cache, open the DNS MMC, right click on the DNS server in the left pane and
choose Clear Cache.

If this fixes it, make sure that your DNS servers have the option enabled to protect cache against pollution. If your DNS servers
are forwarding to your ISP, you may want to remove the forwarders and rely on root hints instead.

Thank you,
Mike Johnston
Microsoft Network Support
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[Ace Fekay [MVP]]

In

We have a problem with Internet access in our company. The
Internet works fine and then all of a sudden it cannot
connect to any site, when we change the DNS settings it
works again for a while and then it stops a week or so
later and we have to change the settings back to the
original and it works again for another few days until we
have to change it again.

Has anyone experienced this proble or does anyone know a
solution to fix it?

Regards,

Dave

More info, as Herb suggested, would be helpful in diagnosing this. If you
could provide us an unedited ipconfig /all from the client, that would be
very helpful. This way we can see the actual configuration and exactly what
IPs are being used and what you are referring to. This will help us greatly.
If you change the names and IPs, it would still leave us questioning.

Also, try what Michael posted about the cache. I think it still comes down
to using your ISP's DNS in your configuration, which is problematic in ALL
cases (not just sometimes), and especially with AD.

Thanks.

--
Regards,
Ace

Please direct all replies to the newsgroup so all can benefit.
This posting is provided "AS IS" with no warranties.

Ace Fekay, MCSE 2000, MCSE+I, MCSA, MCT, MVP
Microsoft Windows MVP - Active Directory