If you have correctly installed the MPTCP-kernel and configured the routing tables as needed, you can start using MPTCP
This server (multipath-tcp.org) is running the latest build of our kernel. Thus, every time you connect to this server you will be using MPTCP.
Download some files http://multipath-tcp.org/snapshots.
You can also visit http://amiusingmptcp.de to see how well your network supports MPTCP on different port-numbers.
No MPTCP at all
If it looks like you don't use MPTCP at all, please check these points:
- Are you using a kernel with MPTCP?
sudo dmesg | grep MPTCP
- Is MPTCP enabled?
- Does the application create an MPTCP connection?
tcpdump -n -i <interface> tcp | grep mptcp
- Is MPTCP blocked somewhere between the client and the server?
MPTCP only with one path
If MPTCP is used but only with one path, please check:
- Did you configure a path manager on the client side to establish more subflows?
sysctl -w net.mptcp.mptcp_path_manager=fullmesh
- Did you configure a path manager on the server side to announce more available IP addresses?
- Did you configure the routing?
- Is MPTCP blocked on some paths?
- See above about tracebox.