rp_filter not work

[Farsya Islami Raishifa]

dear guys,

 

I use banana pi,

root@bananapi:~# uname -an
Linux bananapi 4.2.3-sunxi #2 SMP Sun Oct 11 14:12:18 CEST 2015 armv7l armv7l armv7l GNU/Linux
I have asymetric route, packet go out from one interface and comes in from another interface (tunnel ).

already made 0  for all interface in /proc/sys/net/ipv4/conf/*/rp_filter

ip_forward already enabled.

i dump packet comes in succeed to our banana.

but when i test using ping command, doesn't respond with reply.

any suggest ?

 

thanks

 

 

 

[wildcat_paris]

hello,

just for my curiosity, what is the exact topology of your "asymetric" route, please? Also... route to??? Internet?

[zador.blood.stained]

@wildcat_paris

 

This is "normal" situation when you have multiple network interfaces and custom routing for them. Reverse path filtering applies to incoming packets by checking their source (?) address against current routing tables.

Quote from documentation for rp_filter

Basically, if the reply to a packet wouldn't go out the interface this packet came in, then this is a bogus packet and should be ignored.

Disabling rp_filter should work for asymmetric routing unless there are firewall rules that interfere with this setup.