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View Full Version : Unable to PING but CAN NSLOOKUP..help



Moses
11-07-2003, 03:14 PM
I've got a server which appears to be occassionally loosing its DNS info.
I am unable to PING via Machine Name or IP Address but when I perform an NSLOOKUP via Machine Name it resolves and provides IP Adress. When I perform IPCONFIG I get IP Address and Subnet Mask but am missing Default Gateway.

Any ideas as to what the heck is going on who how to troubleshoot further.
FYI~ I have no access to DNS/DHCP/WINS Servers (Not an Authorized Admin)

Thanks

pave_spectre
11-08-2003, 08:18 AM
Sounds like it could be a firewall somewhere blocking ping.

no-mbr
11-09-2003, 01:00 PM
I can't tell what you are talking about. But a NSLOOKUP, is just that.

It's and answer from a DNS server that a record exists, not that a machine is functioning at that address. You may be receiving a "cached" reply, meaning - it's old info.

Like I said, I can't tell what you are talking about, can you explain? Without a default gateway, it is likely you would only connect to a machine on the subnet of your own network. (if it is subnetted)In otherwords, no internet connections...

It is possible that a firewall would prevent a reply to a ping request. More likely, you have a misconfigured network IP address settings.

Moses
11-11-2003, 04:05 PM
OK I will try to provide more information but I need to know what part of my explanation you don't understand so I can clarify.
Symptoms:
-Unable to ping Server (named jx) from any other machine on network. This includes pinging via machine name and ip address.
-Performing an NSLOOKUP from Server (JX)does provide the name of my DNS Server but it also says dns server request timed out.
-I can ping loopback adapter successfully from JX.
-I cannot ping domain controller or any other machine consistently, I say consistently because sometimes it resolves and other times I get failed to reply, say maybe 50% of the time.
-Event viewer has an error in it stating "amli: acpi bios is attempting to read from an illegal io port address (0x71), which lies in the 0x70-71 protected address. This could lead to system instability." AND "The RPC Server Unavailable"
-I cannot access the network and I am also getting Domain Controller not available messages but I know my DC is up, running and authenticating because all other machines are fine.
Any ideas...thanks

Ghost_Hacker
11-11-2003, 10:39 PM
I would doubt your server is lossing it's "DNS information". First NSlookup will query a DNS server and return the DNS record for whatever computer you looked up. If it returns an anwser then the DNS record for that computer does exist simply check that the information is correct.


amli: acpi bios is attempting to read from an illegal io port address (0x71), which lies in the 0x70-71 protected address.

This points to older BIOS/hardware. I would first recommend you look into upgrading your BIOS.


The RPC Server Unavailable


This points to a service on the local computer that is not running. Check that all services ,on the local computer, that you wish to enable have "started" including the "RPC" (remote procedure call) service.


but am missing Default Gateway

If your server or other computers are on a different network then yours,then a default gateway is needed. Without it you will not be able to access those other computers. (check with your network admin for the correct information.)


If you can't ping or are having 50/50 luck pinging from the troubled computer, but are having no other connection problems from any other computer ,then you need to start your troubleshooting assuming that the problem lies at the workstation and not the server. (Also have you tried pinging your workstation from the server or another computer?)

With that in mind have you tried changing the NIC or the network cable ? Can you hook up the computer to another network connection? Have you ran the netdiag commmand? This will perform a series of test on the computer and check most aspects of it's network configuration.

Get it here (if your computer doesn't have it):
Netdiag (http://www.microsoft.com/windows2000/techinfo/reskit/tools/existing/netdiag-o.asp)

More info here:
Netdiag info (http://www.tburke.net/info/suptools/topics/netdiag.htm)


Good Luck :)

Moses
11-12-2003, 12:08 PM
Ghost_Hacker thanks for the insight, very helpful. Indeed many of the errors I was encountering were infact not related at all.
-You were right on regarding the "ACPI Bios..." error. I flashed the bios and this was resolved.
-The error I was seeing on the DC was due to the fact that my domain is NT 4.0 and my server is 2003 I had to disable "digitally encypt or sign data..." local security policy setting to resolve that error.
-As for the intermittent network failures. I'm a little embarrassed about this one but chaulk it up to experience. I always assumed that a bad network cable would exhibit a complete failure not intermittent failure. After beating my head against the wall I figured I'd change cables for the heck of it, guess what turns out it was the cable....live and learn.

Thank for the tips guys