OK, this is probably best explained with an example. Let's say:
1. The internal interface for the T1 router is 192.168.0.1; and the
internal DSL router interface is 192.168.0.2; and the external IP for the
server farm is 123.123.123.123; and you have an internal workstation IP
address 192.168.0.3.
2. On the workstation:
a. set the default gateway to 192.168.0.2 - this means that any traffic
destined for an IP which is not on the 192.168.0.0 network will go to the
DSL router UNLESS there is a static route to the destination IP.
b. Configure a static route to 123.123.123.123. On the workstation, open a
command prompt and enter this command:
route add 123.123.123.123 mask 255.255.255.255 192.168.0.1
if instead of a specific IP, you wanted to route to a whole
network you would use the 'real' subnet mask, eg:
route add 123.123.123.0 mask 255.255.255.0 192.168.0.1
c. The result is that all non-local IP traffic will use the DSL gateway
EXCEPT for traffic destined for the 123 address (or network) which will
instead be sent to the T1 router.
You can configure multiple static routes if there are multiple incompatable
addresses or networks you want to reach through the T1.
To make a static route permanent, use "route -p add"
If the DSL router supports static routes, you need only configure the static
route on the DSL router (you will have to consult the router documentation
to determine how to do this) - then all clients using the DSL router as a
default gateway will also use the static route. If the DSL router does not
support static route entries, you will have to configure the static route on
each client machine per the above.
Doug Sherman
MCSE Win2k,NT4.0, MCSA, MCP+I, MVP
