Routing server traffic thru two external ips.

Network Administration noc at
Tue Feb 20 13:29:34 CET 2001

   Date: Tue, 20 Feb 2001 10:16:03 +0100
   From: Martin Mares <mj at>

   > I am new and would like to know if this is possible with bird.
   > I currently have a game server setup behind a linux router/firewall which is
   > hooked up to two cable modems via two NICS( eth0 and eth1 ).  The idea is
   > that if I have 12( or more ) players, how do I tell the kernel( with me
   > telling using route ) TX packets to 6 players on eth0 and the other 6 on
   > eth1.  Any thoughts?

   It depends on what your bandwidth requirements are.

   (a) The problem is in outgoing traffic, incoming traffic is minimal

      If both modems are connected to the same provider, the best
      solution is to avoid any routing tricks and just use the load
      balancing features of Linux traffic control.

It probably doesn't matter if the same provider is involved and in
fact, different providers are preferred as that allows some limited
multi-homing.  Load balancing should be employed in any case.  Simply
declaring 2 default routes in Cisco IOS accomplishes that and I
believe that something similar is available in the 2.4 networking.

Fortunately most game programs have higher incoming than outgoing
bandwidth requirements at the player end, which means the reverse on
the server end.  Thus load balancing should be sufficient, but the use
of some of the 2.4 kernel networking features to throttle non-game
traffic (or vice-versa) might be a good idea.

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