2

I cannot reach one of my vendors web sites. I can access the site from home, my boss can access from his home. But, from the office it does not work using the domain name. Using the IP address in place of the domain name does work. From these facts, it seems that I have a DNS problem at my work location. The DNS is obviously not completely dysfunctional as I am able to get to any other domain name that I have tried including some that could not possibly be locally cached. My environment is a windows network with a Server 2003 Standard server acting as the domain controller and hosting the DNS for my intranet. The problem has been going on for two days.

As a developer, I understand the basic concepts of DNS, but am not well versed in the specifics. Nor am I much of an administrator, but unfortunately, I am all we have.

Where do I start?

Jim

Jim R
  • 251
  • 1
  • 5
  • 14

2 Answers2

2

Open nslookup at a command prompt and make sure that it is using the domain controller as a DNS server. Type in the domain name that you're having trouble with and hit enter. Is the IP the same as the one that you can successfully connect to that website with?

Then set nslookup to use an OpenDNS server (208.67.222.222 -- yes, I have them memorized =) ) and query the same domain. Is the IP the same?

If the IPs are different, then we have some kind of DNS issue locally. If not, then we have just entered the twilight zone (the Rod Serling Twilight Zone, not the vampire Twilight Zone).

Incidentally, what type of internet connection do you have? DSL? I had issues with a DSL connection using PPPoE and switching to PPPoA fixed some strange issues with not being able to get to certain domains.

Wesley
  • 32,320
  • 9
  • 80
  • 116
1

Well at the very basic level, if you just want to get it working on your machine, then you can edit your hosts file on your local machine to set the IP address for that name. See this question.

If you want to fix this problem on an organisational level, then you need to get access to your DNS server and take a look at how it's setup and why there is a problem. You need to look for things like:

  • Are the forwarders setup correctly to send queries that this server cannot respond to, to another DNS server normally your ISPs)
  • Is there a DNS record for the domain your trying to reach in your DNS server? This should not be the case, and could be causing the problem.

If everything seems well here, then it may be the DNS server that your requests are forwarded to once your local DNS server decides it cannot resolve them, usually at your ISP, that has a problem. If this is the case you will need to contact them.

Community
  • 1
Sam Cogan
  • 38,158
  • 6
  • 77
  • 113
  • I was aware that I could do the setting in the hosts file. But I do need a solution for the whole organization. I did check the DNS for a record matching the URL that is causing the problem. There was none. I did not expect to find one. I will contact the ISP, was hoping that to be the problem but wanted to make sure that I did my due dilligence before making that call. Thank you very much for the response. I will add comment when problem is completely resolved. – Jim R Mar 04 '10 at 17:14
  • The problem has gone away. Because of some other issues that were going on here at the same time that were totally out fo my control I am unable to definately say that it was a DNS problem at the ISP, but I believe that it was. – Jim R Mar 04 '10 at 20:20