New DC wants to use old DC as internet proxy...

[PrimaryTech]

Hi all!
I'm in the process of migrating from an old Classlink domain controller to a new Server 2003 domain controller. All the clients were set to use the Classlink server as an internet proxy but all of these have been changed to use the SWGfL proxy, all working fine. However, the new DC won't accept the SWGfL proxy for the internet, the only way it will connect to the internet is by using the Classlink server as a proxy.
Sorry it's a bit long winded, my first server migration outside of a test lab, I'm thinking it maybe a DNS issue?
Any help gratefully received!

[FN-GM]

strange one...

What are your firewall settings like, could they stop it?

Your default gateway, is that set correct?

Z

[PrimaryTech]

Default gateway could be it, though I think that it's set correctly in the DHCP scope options as the router's IP. I'll do an ipconfig /all tomorrow and report back...

[Ric_]

Default gateway could be it, though I think that it's set correctly in the DHCP scope options as the router's IP. I'll do an ipconfig /all tomorrow and report back...

You shouldn't be using DHCP to get the IP address for a DC. Check default gateway and DNS settings.

Check your IE settings are correct (even if you don't use IE) and then run

proxycfg -u

to sanitise your sysem-wide proxy settings.

[PrimaryTech]

Default gateway could be it, though I think that it's set correctly in the DHCP scope options as the router's IP. I'll do an ipconfig /all tomorrow and report back...

[PrimaryTech]

Sorry Ric, the DC's IP address is static, what I was meaning by DHCP was that the DNS server is specified in the scope options of DHCP. Thanks for the proxycfg command, I'll give it a go tomorrow!

[Michael]

I suspect DNS is the problem. Your primary DNS should be your new DC and then maybe one or two external DNS servers. There's a possibility the old IP for the Classlink DC is still listed in DHCP.

[PrimaryTech]

It looks like a DNS problem; DNS is installed on the new DC but when I open DNS MMC it says that the DNS server has not been configured. However, I can still see all the forward and reverse lookup zones?

How do I configure the new DC to be a DNS server?

Thanks in advance!

[Michael]

If you're running Active Directory, normally it's recommended to run DNS integrated with AD. Can you verify it is? Open DNS, Expand Forward Lookup Zones, then right click and choose Properties.

If it is, then right click your servername in DNS, choose Properties. Under the Interfaces tab, it should have just your DCs IP address listed. Under the Forwarders tab should be one or two external DNS IPs listed.

[PrimaryTech]

Cheers Michael, there were no IP addresses specified in the forwarders tab, so I put in the two for the SWGfL DNS servers and all is working well. IE now finds the internet using the SWGfL proxy specified in LAN settings.