Can't ping all computers in domain

What is required in order to be able to ping a computer in a Windows domain using TCP/IP? The domain controller is 2000 Server and all client workstations are XP.

I can ping some workstations but not all. On the ones that I can't ping, I tried turning their firewall (AVG) off but this did not help. I'm not surprised about this though because even with AVG enabled, I have it set up to allow ICMP requests so I did not suspect this to be the problem.

Anyone know some other things I could check? Windows services maybe?

Thanks,
Paul

 

I suggest you look at the way the "invisible" computers are connected to the network. If they happen to be connected through a router, it will have a built-in firewall.

Matt

 

Are you PINGing by name or IP address?

If not by name, the problem may be name resolution rather than a problem at the ICMP level. If you are using NetBIOS names (just the computer name) it could be a problem either with WINS or the size or scope of your broadcast domain. If DNS, check that the problem PCs have A records at the DNS server. If not, I'd check the DHCP to DNS configuration.

If you cannot PING by name, can you PING them by IP address?

If not by IP address, the main thing to look is routing issues. For a PING to succeed you need a pathway both to the PC and back (for the reply to pass through). Try doing a TRACERT to the problem PC and see where it fails.

 

I tried pinging by name and IP address which produces the same time out result. The addresses that I am trying to unsuccessfully ping have A records and associated PTR records. Using NSLOOKUP on these computers that I can't ping, I can get the IP address if entering the host name and the host name if entering the IP address.

TRACERT just times out for these computers but shows just the one hop for the computers that I can successfully ping.

We have only about 20 computers connecting into a couple of switches that connect into our gateway firewall. No hidden routers with built-in firewalls. Our gateway firewall is setup to block ICMP packets but that's only for computers outside the firewall - at least that's my understanding. Turning this feature off has no effect on what I am trying to accomplish.

I'm looking into File & Printer Sharing now to see if that might be causing some problems but if there's something I'm missing please let me know.

Thanks guys.
Paul

 

On such a small network, all your devices should be connected directly together via the switches and all be on the same subnet. The only reason not to have them on the same subnet is to block a segment off (to do things like separate the accounts department from the rest of the network).

You have two alternative:

1. Reconfigure the network so that everyone share the same switches and IP address space. The main work would be to reallocate IP addresses to all the PCs (e.g. so they are all in a 10.0.0.0/255.255.0.0 address space) and make sure your switches are connected directly together (not via the firewall). Also make sure that none of the switches have VLANs set up.
2. Identify the device joining your two network segments together and configure it to route traffic correctly. Ensure pathways are set to pass packets both to and from each side of the joining device.

I expect 2 would be easiest to both do and maintain.