Unable to reach certain websites DNS issues

Today I started having issue with my DNS resolution and can't quite find out how to fix this issue. I have two DNS servers on my network and the primary domain controller cannot reach UPS.com but the secondary server can. On the primary server I can reach most sites but when it comes to UPS it cannot. I have restarted the server and checked the DNS settings on the NIC and all looks good however I am unable to reach UPS on that computer and since this is the primary domain controller my users cannot access the site either.

What can I do to find out what is causing this configuration error

TimSr. System AdminAsked: 2016-10-03

Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

Experts Exchange Solution brought to you by

Enjoy your complimentary solution view.

Get every solution instantly with Premium. Start your 7-day free trial.

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Melissa DyerSenior Network AdministratorCommented: 2016-10-03

First you need to clear the DNS cache. Run the following command: ipconfig /flushdns
Next make sure that the DNS server is using itself as the primary DNS and the secondary server is the other INTERNAL DNS server. Next verify that the forwarders setup are valid and responsive. Good luck!

TimSr. System AdminAuthor Commented: 2016-10-03

Flushed the DNS and restarted both servers. The primary server can get to the UPS website but the secondary cannot. When I ping the ISP DNS servers the first server times out half the time and the secondary never times out. Could that be the issue? It really doesn't explain why one server can reach the same site while the other cannot.

LVL 29

DrDave242Senior Support EngineerCommented: 2016-10-04

When I ping the ISP DNS servers the first server times out half the time and the secondary never times out. Could that be the issue?

It certainly could. If the "primary" DC has the ISP DNS servers configured as forwarders but is having issues connecting to them, it's most likely not getting responses to DNS queries that it forwards to them either.

Figuring out why you're having intermittent connectivity problems with the ISP DNS servers may be a real pain (the ISP is pretty much guaranteed to say it's not their fault, especially since your other DC doesn't seem to have the same problem), so in the meantime you may want to consider either using a different set of DNS servers as your forwarders (Google's 8.8.8.8 and 8.8.4.4, for example) or removing the forwarders altogether and using root hints instead.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial