ROUTE ADD problems on 2003 multihomed system.
Posted on 2004-08-24
We needed to connect a 2003 system to another network via VPN. The VPN network originally had the same IP scheme as the 2003 network (10.0.0.0/24). Using a NAT device on the VPN network side, we were able to present a different scheme (172.16.254.0/24) to the 2003 side.
The 2003 side now needs to present a different scheme to the VPN side. We chose 172.16.252.0/24. We *cannot* install a NAT device on the 2003 side, so we multihomed the 2003 system:
NIC 0x1 - 10.0.0.2/24, gateway 10.0.0.1
NIC 0x2 - 172.16.252.2/24, no gateway defined
Both are plugged into the same switch.
10.0.0.1 is a firewall with VPN set-up to the 172.16.254.0/24 network. The VPN is negotiating and passing traffic.
I am attempting to route traffic from the 2003 system to the VPN network. 172.16.252.2 -> 172.16.254.3, and vice versa.
Receiving packets on the additional interface is no problem. It ARPS fine to the firewall and *receives* data all day long.
*Sending* data is the problem. The default route uses the 10.0.0.2 interface. Attempting to add a route to use the additional interface for VPN traffic:
ROUTE ADD 172.16.254.0 MASK 255.255.255.0 10.0.0.1 IF 0x2
"The route addition failed: Either the interface index is wrong or the gateway does not lie on the same network as the interface. Check the IP Address Table for the machine."
This is a stumper. Any ideas folks???