TCPIP Delay

waltforbes
waltforbes used Ask the Experts™
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Points of My Scenario
1. I am admin of a Windows domain (Server 2003 AD)
2. Member servers run Server 2003 or Server 2008 R2
3. One of my 2008 R2 member servers consistently shows delayed response contacting systems: When I ping a host for the 1st time from this server, I get one "Reply from <itself>: destination host unreachable", followed by 3 proper replies.
4. This server periodically sends groups of files to another system, but the 1st file in the group always gets dropped (just like the 1st ICMP/ping packet).
QUESTION: How do I stop this behavior (first data packet dropped)?
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Top Expert 2012

Commented:
ipconfig /flushdns

Verify that you can do an nslookup from the Windows 2008 machine to the machine you are doing the file copies and that the lookup doesn't take a long time (should happen as soon as you hit enter on the keyboard.  If you have to wait for even a second that's too long).
waltforbesSenior IT Specialist

Author

Commented:
To xDUCKx: I did a "ipconfig /flushdns", and I checked nslookup - sucessfully. However, the issue still remains.
Commented:
It seems likely it is not a DNS issue but a problem with slow ARP resolution.

When the server want to send a ping, or file, to an IP address it must first find out the MAC address of that PC/server - or if the IP is outside the subnet of the server, the MAC address of the default gateway.

Slow ARP could be a sign of a somewhat overloaded broadcast domain - especially if all servers and PCs are in the same subnet.
waltforbesSenior IT Specialist

Author

Commented:
Resolution: server moved to same subnet as target host.

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