IE Initial DNS query always goes wrong

[dtakias]

Hi

 

A primary school in the South runs an AD network with Win2K3 SP2 which I am responsible for. I am having a weird and very annoying problem and whatever I have tried I cannot solve it.

 

When users startup IE it takes ages to resolve the homepage and finally it fails. If they press stop and refresh it works just fine. I have tried flashing the dns on the terminal and server, looking at the logs with no success. The server is fully updated. The problem does not appear on the server, only on the clients and only when they start it. Because of that I have been forced to install firefox community edition which works fine.

 

Please advise if you have any ideas!!!

[sahmeepee]

If the homepage is internal, make sure it's in the proxy exclusion list in IE?

[tom_newton]

You using proxy.pac or anythin like that?

[dtakias]

Yes we use an auto configuration script or proxy settings. No matter what i try its still the same thing. The weird thing is that it only happens with Internet Explorer with both versions 6 and 7. Firefox works just fine no matter what setting I choose. And as I said before IE works fine on the server itself. So I am suspecting it has to do with the AD or DNS configuration on the Server.

 

Any more ideas?

[dtakias]

If the homepage is internal, make sure it's in the proxy exclusion list in IE?

 

 

The homepage is not internal and no matter what page I choose its still the same thing

[SYNACK]

Sounds like the "Automatically detect settings" box may be checked, this could be the cause of the delay.

[dtakias]

i have tried that as well. basically it is able to resolve to the IP address but after that nothing happens

[SYNACK]

Have you tried running an "nslookup www.sitename.com" at the command prompt to check that the lookup is happening quickly enough and returning the proper results. Also are you using the ISA firewall client as this could be causing the issue if the ISA server is experiencing an issue.

 

You could also try connecting to a site with "telnet http://www.google.com 80" then typing in "get" and see if it spits out the html code or if you get a server error. This will only work if your proxy is set up to work transparently though.

[sahmeepee]

What proxy/firewall are you using and what version?

[dtakias]

Have you tried running an "nslookup www.sitename.com" at the command prompt to check that the lookup is happening quickly enough and returning the proper results. Also are you using the ISA firewall client as this could be causing the issue if the ISA server is experiencing an issue.

 

You could also try connecting to a site with "telnet http://www.google.com 80" then typing in "get" and see if it spits out the html code or if you get a server error. This will only work if your proxy is set up to work transparently though.

 

 

Sorry it took ages to reply. I have tried nslookup and is returning the proper results. The internet comes from Hampshire LEA and I suspect they use ISA Server. Although its only this school which has this weird problem. I suspect it has to do with the Server configuration.

[dtakias]

What proxy/firewall are you using and what version?

 

 

As I said the network comes from the local LEA so its fully filtered and the school is a primary school so we dont need to do extra filtering.

 

Is there a way to test the server configuration and maybe post the results here so you guys can tell me your opinion? I think i could use netdiag and dcdiag although I am not sure about the right switches I should use..

[sahmeepee]

You could run RSOP.msc on one of the affected machines and then post the relevant sections of the results..

[dtakias]

You could run RSOP.msc on one of the affected machines and then post the relevant sections of the results..

 

ok i will do that tomorrow during my visit to the school

[charliem]

Hi

 

I am experiencing exactly the same issue. The initial lookup seems to fail but then if the page is refreshed or if you manually type in the URL (incidentally the school website which is hosted externally) it loads the page absolutely fine.

 

I have checked the group policies which seem fine and all of the above. We are using smoothwall but my machine has a proxy exception and it is still happening which makes me think it's a DNS issue. Any ideas...

 

Thanks

[srochford]

What's the DNS setting on a client machine? (ipconfig /all at a prompt will tell you)

 

The answer should only show internal DNS servers. If it doesn't then change the DHCP server to give out the IP of your internal DNS. If it does give out the correct internal address then check the DNS server and see if it's using forwarders or root hints. If forwarders, are they correct? (I'm guessing they should be the same as your other schools - they need to point to an external DNS server). If root hints, are they correct?

[dtakias]

Hi

 

I am experiencing exactly the same issue. The initial lookup seems to fail but then if the page is refreshed or if you manually type in the URL (incidentally the school website which is hosted externally) it loads the page absolutely fine.

 

I have checked the group policies which seem fine and all of the above. We are using smoothwall but my machine has a proxy exception and it is still happening which makes me think it's a DNS issue. Any ideas...

 

Thanks

 

Hi charliem

 

I had to delete and re configure my DNS settings. Then problem was fixed. As srochford suggested please check.

[charliem]

Hi dtakias (and srochford)

 

Thanks for the help. I'll do as you suggest

 

Cheers