Simetimes I get "No messages received" and have to retry

Sometimes I have to retry several times until sockperf starts to send. I repeat the same line, and after a few tries, it starts sending.
I'm using this on the server:

sudo sockperf sr -i 239.1.1.1 -p 10000 --mc-rx-if <IP1>

and this on the client:

sudo sockperf pp -i 239.1.1.1 -m 64 --mc-tx-if <IP2> -p 10000 --full-log data.csv -t 10

[igor-ivanov]

Hello @fsuarezo. Do you see traffic using tcpdump on both sides?
Could you remove --mc-rx-if and --mc-tx-if if you do not actually need them.

It is a bit more complex.
We created a software switch that can be used on different clouds and allows the MC traffic to be transparently used on existing software solutions. The agents use a virtual NIC, and we need the --mc-XX-if to tell sockperf where to send the MC traffic.
We have a monitoring tool that shows the traffic that goes on the interfaces and the switch so we know when the traffic is passing thru or not.
But as the traffic has to be modified in order to travel on the clouds (MC traffic is dropped), we can't use tcpdump freely as we want. Under certain conditions, we can use it, and sometimes not.

Anyway, what annoys me is that retrying the same sockperf command sometimes goes OK, and sometimes no.

[igor-ivanov]

sockperf is socket based application that opens socket and do send operation. Did you check your interface/switch settings? Are you able to use ethtool –S <dev>?