How can I start debuging?

[multipath-tcp]

How can I start debuging?

[gdetal]

What type of application/traffic do you use/generate ? Is it HTTP download or upload ?
If it is HTTP, are you sure that MPTCP works ? Is http://amiusingmptcp.com showing a big green YES ?
Do you have policy routing configured ? (output of ip rule and then ip route show table XXX)

[yuemingjiang]

gdetal, Thank you very much!
I can see the "Yes! You are all set to use MPTCP on this device!....", although the net speed is very very slowly.
Which application can be used for testing? If MPTCP can boost the network, the server must support MPTCP, right?

[gdetal]

@yuemingjiang there is an iperf application available on android that you can use or download from an MPTCP-enabled HTTP server.
You didn't answer my last question: do you have policy routing configured ?

[yuemingjiang]

@gdetal I didn't configure routing policy manually, I think netd do this. I port android_external_iproute2 and android_system_netd to my Android phone.

[yuemingjiang]

cat /proc/net/mptcp
sl loc_tok rem_tok v6 local_address remote_address st ns tx_queue rx_queue inode
0: 3DEBDB7B 3DEBDB7B 0 0900A8C0:E544 29D01C3C:0050 01 01 00000000:00000000 20948

[gdetal]

netd does not by default enable 3G and WiFi and does not configure policy routing. Did you modify netd ?

[yuemingjiang]

@gdetal, I check the 3G and WIFI status, they are enable, I can "ping -I rmnet0 ..." and "ping -I wlan0 ..." meantime.
But about the policy routing, I have no idea how to configure it, now it behave as default setting.

[gdetal]

Look here then: https://listes-2.sipr.ucl.ac.be/sympa/arc/mptcp-dev/2014-01/msg00027.html

[yuemingjiang]

@gdetal Thanks!
I already install this APK, and enable 3G + WIFI at the same time.

Do you have any guideline about the policy routing configure?

[gdetal]

The APK should configure automatically the policy routing, please give the output of ip rule show.

[yuemingjiang]

root@hammerhead:/ # ip route
default via 192.168.0.1 dev wlan0
default via 10.73.105.33 dev rmnet0
10.73.105.0/26 dev rmnet0 proto kernel scope link src 10.73.105.32
10.73.105.33 dev rmnet0 scope link
74.125.235.195 via 10.73.105.33 dev rmnet0
192.168.0.0/24 dev wlan0 scope link
192.168.0.0/24 dev wlan0 proto kernel scope link src 192.168.0.9 metric 321
192.168.0.1 dev wlan0 scope link
210.21.196.6 via 10.73.105.33 dev rmnet0 src 10.73.105.32
221.5.88.88 via 10.73.105.33 dev rmnet0 src 10.73.105.32

root@hammerhead:/ # ip rule
0: from all lookup local
99: from all to 10.73.105.33 lookup main
99: from all to 74.125.235.195 lookup main
32766: from all lookup main
32767: from all lookup default

[gdetal]

It seems that the policy routing is not configured at all. Have you executed and enabled the application from the APK ?

[yuemingjiang]

@gdetal Yes, I executed and enabled the application from the APK. I will check the command sent by APK now.
Thanks!

[yuemingjiang]

@gdetal I don't think APK can auto configure the routing policy. It just send following command:
ip link set dev wlan0 multipath on
ip link show dev wlan0
ip link show dev rmnet0

Do you have any idea to configure the routing policy manually?

[gdetal]

The app is supposed to do it. Do you have rooted your phone (it requires su) ?

To do it manually you have to follow: http://multipath-tcp.org/pmwiki.php/Users/ConfigureRouting

[yuemingjiang]

@gdetal Yes, I have rooted my phone, and can see the APK sending command to iproute2.
I follow the guideline, but an error encountered when I set

ip route add default scope global nexthop via 192.168.0.1 dev wlan0
RTNETLINK answers: Invalid argument

By the way, wow, You are the author of android_packages_apps_MPTCPControl-ics!! You are a Great man!

[yuemingjiang]

@gdetal Until now, I'm confuse about mptcp. One quetions:
Apk on Android phone with MPTCP create several sockets to download file from Internet server, if the server is not MPTCP enable, then 3G & Wifi interface can downloading in same time?

[gdetal]

No it does not. It only enables the fact that 2 interfaces are up and running and that the routing is correctly configured such that MPTCP connections (so to an MPTCP-enabled server) can use both paths.

[yuemingjiang]

@gdetal Thanks! Your kindly help is very useful.
I need a technical which can boost download speed from a normal server( mostly is MPTCP unable ) via 3G + Wifi. So I think MPTCP is not match my requirement.

[gdetal]

Indeed, there are download boosters that are available on android (as the one advertised by Samsung for the S5). These solutions are based on multiple HTTP range requests. See https://play.google.com/store/apps/details?id=it.opbyte.superdownload

I am closing the issue as in the end it is not related to MPTCP.