Routing not working

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On 05/31/2011 09:29 AM, Tom Horsley wrote:
> On Tue, 31 May 2011 14:17:44 +0100
> Dan Track wrote:
> 
>> Just for future reference I figured out the problem. You need to run
>> on rp_filter on the interfaces you wish to include in the routing
>> process.
> 
> What exactly does that mean, and how do I do it? I've never
> heard of it before, but it could easily be the reason
> I haven't been able to get my USB wi-fi dongle working
> as an access point in f15 while doing all the exact same
> things I did in f14 (where it works perfectly).

  rp_filter (/proc/sys/net/ipv4/conf/*/rp_filter) attempts to avoid src
IP spoofing by checking src IP of packet and ensuring that it goes out
the way it came - to be a little more specific - if the 'best route' to
that src ip is not the same interface the packet came in on, rp_filter
will drop the packet.

  Usually its fine (correct) to leave rp_filter on - be thoughtful if
you're doing something funky with routing tables.

  Thats my recollection anyway ... you turn it on/off echo 1/0 into the
/proc/sys/xxx

  gene/