Deterministic routing / two outbound routes, two different IP addresses
Posted on 2006-05-31
I have posed this question to Cisco - awaiting an answer but figured someone has already had to figure this one out. The question is I have 1 point-to-point T1 coming into the office with an IP scheme of 10.210.38.x; I have another T1 going to the internet with an IP scheme of 10.5.10.x. These are two physically seperate networks and I want to merge the two. Basically, the P-P T1 (10.210.38.x) is apart of another network, a WAN. We use application on that network that require routing to local machines on that network (telnet, custome applications using IP addresses, etc.). Almost all the computers are on that network now, but thay must use that network for internet access and go through that network. This is basically what I want to do:
10.5.10.X ------------------->Cisco 3750 / L2 Switch---------->Cisco 1700 / PIX 515e -------------> Route to 10.210.38.x for those applications - 10.210.38.x
(Have two CSU/DSU mods) ------> Route all other traffic outbound (internet) - 10.5.10.x
I understand that each module interface will also have to NAT from internally.
Another question is does the internal address have to be the same (inside network) as the outbound leg? Another question is what additional hardware may be needed to this to work. Initially, Cisco believed that no additional hardware other than another CSU/DSU module is needed. I want to know if the 3750 should also be upgraded to L3 capabilities to help routing.
Another way to look at it is that application that access 10.210.38.x needed to be routed to a specific CSU/DSU and be able to establish a route back; all internet bound traffic (https/mail) needed to be routed to the 10.5.10.x outbound leg.
Any help to clarrify this would be helpful - not necessary to be cisco specific.