# Solved: Server 2000 blocking ARP & Ping



## Chris-Staples (Aug 12, 2009)

I have a windows 2000 server (just recently moved locations but no IP changes or LAN changes) that is reachable via Start - Run - \\servername but not \\IP . Getting to shares work, user drive mappings from login script work, and printing works on the server.

The things that happening are: inability to RDP, Ping, and the monitoring group can't see it.

The issue one of our Network Engineers and I found is that the server will not reply to the network's ARP request. Thus the switch's Show ARP command shows the IP, but where MAC should be is "Incomplete". When you do a Show MAC address-table the MAC shows up as normal with the Port it is plugged into.

I believe this ARP issue is the cause of all the issues. We have asked one of our Windows Server Engineers to look through the DRAC (which is reachable) but have not heard back. We think it is something with the Server Firewall or a service on the device that is causing this. Anyone know which service this might be since I may end up having to travel there to try and fix it.

The network engineer and I can't understand how it is still reachable with ARP not working.


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## DariusSupport (Apr 5, 2011)

if it is blocking ping then icmp packets needs to be let through. If you can reach the server by name and share, but not an IP address check netbios over tcp/ip and the dns server, sounds like the reverse lookup is working yet the forward lookup is not. try flushing the dns on local machines.


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## Chris-Staples (Aug 12, 2009)

The DNS resolves to the correct IP it just that the switch doesn't know how to get to it VIA IP. I believe the ARP issue is causing the inability to Ping since the network is not able to resolve the IP to the MAC address. Once the switch can tie the IP to the MAC address it should be good.

But I will see if the Server Engineer will take a look at the NetBios.


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## Chris-Staples (Aug 12, 2009)

Issue was that the Server team had the 2nd NIC set to DHCP instead of the propper IP address. So when server was moved the network cable was put in NIC 2 and not NIC one. So if you used the name DNS would resolve via the DHCP entry.


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