RR scheduler not working when using an MPTCP proxy

[GinesGarcia]

Hi,
I have a deployment where MPTCP is enabled between a client and a SOCKS proxy with two available paths. The latter is in charge of provide internet connectivity.

When downloading a file from the client, the scheduler in the proxy is not sending packets following RR, it send packets through one subflow instead. what could be the problem?

I have already checked that RR is correctly working by sendind traffic from proxy to client with Iperf tool.

The configuration I have in both client and proxy is fullmesh path manager and rr scheduler.

Thanks in advance,
Ginés.

[cpaasch]

Do you have a packet-trace of this behavior? Thanks!

Btw., we discourage using the RR scheduler, as it is not using the paths in an efficient way and will lead to a slow experience.

[GinesGarcia]

Hi,
attached you can find the packet-trace during an iperf between the client and the proxy (still with the same behaviour).
In the pcap files you can see icmp "destination port unreachable" packets because I only want to allow subflows between two interfaces, not all of them. As you can see, almos all the traffic goes through the first path and it must be shared between paths because of the roundrobin scheduler.

Regarding your suggestion, I'm using RR because our goal is more related to behaviour than performance, but of course, the performance is way worse.

Thanks in advance,
Ginés.

rr.zip

[cpaasch]

Which kernel are you using?

[GinesGarcia]

4.14.41 compiled from source

[cpaasch]

I see - I will try to find time to look into this.