[LARTC] custom routing (two gateways)

[Christian Parpart <trapni@gentoo.org>]

[-- Attachment #1.1: Type: text/plain, Size: 1834 bytes --]

Hi all,

i'm having a somewhat stupid problem I can't get rid of.

we've a server that accepts incoming world connections 
from a load balancer (10.10.10.4) to port 80,
and we still want to serve incoming ssh/http from the firewall (10.10.10.1) 
routed to this host (10.10.10.90) and their reply packets of cause shall be 
send out through the firewall.
unfortunately, both hosts (the load balancer (LB) and the firewall(FW)) are on 
the same subnet (10.10.10.0/24) and though on the same interface (eth0), but 
I need to find a solution.

So, packets send from the LB shall get their answer through the LB as nexthop 
of couse, as well as incoming packets from the FW shall have response packets 
send out to the FW as nexthop, too.

But how to realise this?

server:           10.10.10.90 (this is the problem host)
firewall(FW):     10.10.10.1 (we receive (mostly) ssh/https conns from it)
loadbalancer(LB): 10.10.10.4 (we receive http conns from it)

FW and LB are accepting/forwarding and routing connections from the world to 
our server.

server ~ # ip route list
192.168.0.0/24 dev eth1  proto kernel  scope link  src 192.168.0.90
10.10.10.0/24 dev eth0  proto kernel  scope link  src 10.10.10.90
127.0.0.0/8 dev lo  scope link
default via 10.10.10.1 dev eth0

You see, default traffic is routed through the firewall as the default 
gateway... but now, we want to have outgoing traffic caused from incoming 
packets from the load balancer to be routed back through the loadbalancer 
itself.

I tried here several approaches, like adding custom routing tables, and 
modifying the tables (including main) either I got no answers routed to the 
FW or no traffic got routed to the LB.

Can you please give me a hint on how to find the right way?

Thanks in advance,
Christian Parpart.

[-- Attachment #1.2: This is a digitally signed message part. --]
[-- Type: application/pgp-signature, Size: 189 bytes --]

[-- Attachment #2: Type: text/plain, Size: 143 bytes --]

_______________________________________________
LARTC mailing list
LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc