Multiple NICs + GW's

["Michael Bellears" <MBellears@staff.datafx.com.au>]

I have a test webserver with two NICs:

Eth0: xxx.xxx.ba.3/24
Eth1: xxx.xxx.bb.115/28

Route Table:
Destination     Gateway         Genmask         Flags Metric Ref    Use
Iface
xxx.xxx.bb.112  xxx.xxx.bb.113  255.255.255.240 UG    0      0        0
eth1
xxx.xxx.bb.112  0.0.0.0         255.255.255.240 U     0      0        0
eth1
xxx.xxx.ba.0    0.0.0.0         255.255.255.0   U     0      0        0
eth0
0.0.0.0         xxx.xxx.ba.254  0.0.0.0         UG    0      0        0
eth0


Eth0 is directly connected to core router, which has an IP of
xxx.xxx.ba.254
Eth1 is connected to a Loadbalancer, which has an IP of xxx.xxx.bb.113
(Which is connected to core Router)

Core Router has route for xxx.xxx.bb.112/28 -> xxx.xxx.bb.113

Traffic from external:
Connections to xxx.xxx.ba.3 are all successful.
Connections to xxx.xxx.bb.115 all fail.

Connections to xxx.xxx.bb.113(Loadbalancer) are all successful.

If I run tcpdump on eth1, I can see the traffic hitting the webserver,
but it never returns - It appears to throw it back out via the
webservers default gw (xxx.xxx.ba.254).

FYI: I have another test webserver (Single NIC), sitting behind
loadbalancer, with IP of xxx.xxx.bb.114/28 (Def. GW xxx.xxx.bb.113)
which can successfully be contacted from external.

Is there anyway I can force traffic to go back out via the NIC it came
in on?

Regards,
MB