Cannot ping Internet, IP or Website name

[Newbee04]

Hello,
I support a small company network and over the weekend I made changes to my DHCP scope since I wanted all machines on the network on the same subnet. Most machines were on class A, and only two servers were on B, including the DC. I made the change on the DC so all computers would be on class B via DHCP. After the change, 4 machines out of 20 could not get to the Internet, I can't even ping website names or IPs. I can on the rest of the machines though. Running Ipconfig/all shows that on these machines, there are no listings for DNS and the default gateway IP is blank. I tried removing the winsock reg valus and running winsockxpfix.exe to no avail, among numerous other things. I just can't figure out why only 4 machines are having this problem. I can ping machines on the internal network but cannot ping machines on our other network, which I can do from the machines that are working on the local LAN. Any suggestions on this one? I tried just about everything from disabling firewall (all machines are XP), removing and installing NICs (since these laptops have built in LANS) checking for viruses, spyware, etc...nothing will work..please advise...

 

[chieftan999]

I assume because you can ping other machines on the LAN that you have tried both their IP addresses and their FQDN's.

If, when you perform an IPCONFIG /ALL, there is no gateway address showing then you will NOT be able to get out onto the WAN.

Have you tried manually configuring these machines? If you manually configure them with an IP address and a subnet mask, a gateway address and a DNS address and try again, what happens? If it all works then this must have something to do with your DHCP scope or addressing.

Reamin positive. The affect on those around you will amaze.

 

[Newbee04]

All works well with manual configuration, but this is really only a temporary fix, I still need to get to the root of the problem. The problems began when I changed the scope on the DHCP server, so everyone would be on the same subnet. I don't see where there are any other changes that can be made to the scope to get things working, especially since the majority of the computers on the network are ok (only 4 machines are having this problem). Any other ideas? Thanks for your input.

 

[Serbtastic]

What happens when you do an ipconfig release/renew on the 4 non-working machines? Do they get a valid gateway and dns servers? Perhaps you could post an ipconfig /all from a working and non-working machine for comparison.

 

[Newbee04]

Tried that, didn't work.....but... FINALLY figured out what was wrong about 10 mins ago. The Server settings under DHCP scope weren't configured with the correct router IP. Why only 5 machines were affected remains a mystery, unless the remainder of the machines were using cached information, or never rebooted as requested. I entered the correct information and rebooted my test unit. Low and behold the Gateway and DNS information appeared!

 

[bcastner]

Windows is at times lazy about forcing a DHCP request:

http://support.microsoft.com/default.aspx?scid=kb;en-us;167014&Product=win2000€