Need help in iperf command for sending the IPv6 multicast traffic on Ubuntu

[svnas1994]

Hi All,

I am trying to send the multicast traffic with Ubuntu PC on IPv6 address. But I don't see the Packets in Wireshark .
I am using the below command.

Ubuntu PC is running on 24.xx (Also tried with other Ubuntu PC's. But the behavior is same)

iperf -c ff0e::101 -p 6001 -u -V -i1 -T32 -l 1450

Can someone help on resolving this issue.

This PC is able to receive the multicast data but unable to send it. So Need help on the same.

TIA,
Sairam

[davidBar-On]

Hi, note that this is iperf3 forum and your question is about iperf (iperf2).

Regarding your question, it works on my local WSL (Windows Linux using Ubuntu). I am not familiar with how iperf2 implements Ipv6 support, but some questions/suggestion that may help understanding the problem:

1. If I understand correctly, the client successfully connect to the server and sends the UDP packets. Were do you run the Wireshark? On on the client machine? Server machine? Router?
2. Can it be that some kind of firewall blocks the UDP packets?
3. Try using other IPv6 addresses, e.g. ff0e::2 or ff0e::e, to see if there is a difference. If I understand IANA IPv6 Multicast Address Space Registery, ::101 is allocated for NTP.
4. Try binding to a specific network port, e.g. ff0e::101%eth0.

[bmah888]

Closing this issue, as noticed by @davidBar-On the question pertains to iperf2, and this Github project is iperf3.