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I have two servers on the same subnet. I have an application installed which uses multicast UDP to propagate events between the two servers and keep them in sync.

This does not seem to be happening, so I want to make sure that the multicast UDP messages are getting through as my first step.

The servers are running Windows 2008 R2.

How can I test Multicast UDP connectivity between two servers?

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up vote 12 down vote accepted

Try iperf

An article that explains the different steps:

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Perfect, thanks! A Windows binary is linked from this article: – Greg B Jul 26 '11 at 14:13

iperf is a great tool, but could be a long procedure in installing it; Most repositories don't have this package. Depending on your Distribution, netcat is available in mostly every repository

You can also use netcat :

Server: nc -lu -p PortNr

Client: nc -vzu ServerIP PortNr

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+1 Ah! Awesome! I'm gonna try this! – Viet Dec 27 '12 at 21:07
This will not work for UDP Multicatst. I tried it with a MC address like and nothing happens. Also strace on it doesn't show any ADD_MEMBERSHIP operation. Multicast is also missing in man nc. I suggest sockperf - see below. – avner Jan 14 '14 at 11:04
example with socat: socat UDP4-RECVFROM:9875,ip-add-membership=,fork - |hexdump – Francois Apr 16 '15 at 14:11

I highly recommend sockperf

It's a great tool for checking performance with both TCP and UDP, including UDP Multicast.

Example of a multicast UDP stream:

  • on the server: sockperf server -i -p 1234
  • on the client: sockperf ping-pong -i -p 1234
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You can use SimpleMulticastAnalyzer - it's a simple .net multicast application that I wrote.


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