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Re: Fw: Can a daemon listen only on some interfaces?

Plato <tom@redant.freeserve.co.uk> writes:

> > >         echo 1 > /proc/sys/net/ipv4/conf/*/rp_filter
> > > with    echo 1 > /proc/sys/net/ipv4/conf/*/log_martians
> > > for logging/fun purposes.
> > 
> > rp_filter will not help with that.
> I thought that rp_filter was for precisely this. Doesn't it stop packets
> which appear on interfaces with invalid IP addresses for that interface
> from getting through?

It's a return-path filter; if flipping the src/dest IP#s wouldn't send it
back out the same interface, it doesn't come in at all. 

So a specially routed packet from a.b.c.d -> coming in on eth0
becomes a             packet from -> a.b.c.d going back out

That certainly looks wrong to me, although I'm not /sure/ it would produce
the required interface conflict for rp_filter.

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