Re: Losing connection between nat and filter tables

[Mart Frauenlob <mart.frauenlob@chello.at>]

On 09.05.2014 23:07, netfilter-owner@vger.kernel.org wrote:
> No deal yet. After inserting the new routing tables and rules it didn't
> really change anything.
> The eth2 doesn't have a gateway set in the config file, only eth1 have
> it. Plus, these two interfaces are in the same subnet and there's only
> one gateway on it (180.1.2.1).
>
> [root@firewall ~]# ip route show table T1
> default via 180.1.2.1 dev eth1
>
> [root@firewall ~]# ip route show table T2
> default via 180.1.2.1 dev eth2
>
> [root@firewall ~]# ip rule show
> 0:      from all lookup local
> 10:     from 180.1.2.11 lookup T1
> 20:     from 180.1.2.12 lookup T2
> 32766:  from all lookup main
> 32767:  from all lookup default
>
> (I had to add the tables T1 and T2 in the file /etc/iproute2/rt_tables)
>
> Even so, I see it reach the PREROUTING chain in eth2 but it still
> disappears after that. Connections reaching in the eth1 still works.
>
> There's something else to try?

Check values of /proc/sys/net/ipv4/conf/*/rp_filter
and disable them.
To use the TRACE target just put a -j TRACE on the desired place.