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Troubleshooting dropped packets

Hi Network experts :-)

I had a simple query I was hoping you all could help me with. We have two servers that need to speak to each other, AppServerA and AppServerB. However, I notice that the "communication line" is sometimes reset because one of the servers states that it has recvd no response from the other.

The vendor says we need to measure for packet loss between the two servers.

Problem is, the issue is very intermittent, so it's not like I can run ping and I will see one of the four packets dropped.

Does anyone know any utility that I can use to measure packet loss over the course of, say, a day? I just want to see if there really is packet loss, or if the application is for some reason timing out.

Also, any way to measure if the bandwidth is getting saturated and that is what's causing the disconnection?
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One simple way to do it would be to use the command

ping yourserver -t  > logfile.txt

This will cause the server to ping until you press control+c and it will log the output of the ping to a text file.
View this file to find out when the problem occurs.

Are these servers on the same LAN or on different networks?
Commented:
Install Wireshark and capture all the packets

Do that on both servers

Author

Commented:
Thanks all!

skykingjwc: Thanks - that would work but I think we need to leave this running all day. Is there anyway we can use the logfile.txt to find at what point in the day (i.e the time) the packets were dropped?

rharland2009: On the WAN

tcomp: I'm not familiar with Wireshark - will installing this on the server have any adverse resource effect at all?
Try this.
Make a batch file with the following text.

:start
@echo off
time /t
ping www.yahoo.com

goto start


Name the file pingtester.bat.  Name it something else.
Then run it from the command prompt like this  
 pingtester.bat > logfile.txt

Replace yahoo.com with your servers name or address.
Ignore the "Name it somethign else" sentence in my last reply.

Commented:
No wireshark will not affect the system.

It is free and the best tool for properly capturing and inspecting packets and packet loss.

Author

Commented:
Thanks guys...out of interest does anyone here recommend using NetMon as opposed to Wireshark? Netmon seems to be widely used by the network guys here and I was wondering why?