A replacement for rp_filter with iptables (config help needed)

Jozsef Kadlecsik kadlec at blackhole.kfki.hu
Mon Jul 4 09:39:16 CEST 2005

On Sun, 3 Jul 2005, Jan Engelhardt wrote:

> >> iptables -t mangle -A PREROUTING -i ! eth1 -s
> >> 2xx.xx.xxx.224/ -j DROP
> >
> >If you support 2.6.x kernels, I'd suggest to use the raw table instead:
> >thus the unnecessary load on conntrack could be avoided.
> Why use this sort of replacement for rp_filter anyway? What's bad with
> rp_filter? (Apart from the problem with asymmetric routing, as is mentioned
> in net/ipv4/*.)

Thus one can disable rp_filter and collect the logs together with all
the "other" firewall log entries.

Best regards,
E-mail  : kadlec at blackhole.kfki.hu, kadlec at sunserv.kfki.hu
PGP key : http://www.kfki.hu/~kadlec/pgp_public_key.txt
Address : KFKI Research Institute for Particle and Nuclear Physics
          H-1525 Budapest 114, POB. 49, Hungary

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