[FW1] 2 Firewall & One DMZ

[Gunjan @ chat4help]

Hi, We have two WAN links (with diff. IP range) and my servers are in DMZ area, and I want that request comming from both the Links goes to the same server in my DMZ, and I'm doing NATting also(I don't think that there is any other way to do this , except NATting) My structure looks like this: 100.x.x.1    10.x.1           10.x.x.2 ISP1 ---- FW1 ------------|  DMZ                |                 |              LAN              | Server                |                 | ISP2 ---- FW2 ------------|  here 200.x.x.1     10.x.10 On my DMZ server I specify defalut route from both the FW: ie : route 0.0.0.0  10.x.x.1 AND  route 0.0.0.0 10.x.x.10 Now I saw strange behaviour, some time request commig from FW1 lost or some time from FW2 lost. What could be the reason of this?  As I could understand that if request come from FW1 with the real IP (not 10.x.x.) and replies might goes back from FW2 (b'cuz  system have two default route) then It lost because FW2 does not have any entry for this request, and don't reaches to the client.(because request for this is on FW1) I'm accessing Database in my DMZ. Can we fix the route for a particular request/session, if request comming from FW1 then reply should goes out only from the route (FW1), not from the other route (FW2). How  can I solve this problem? Thanks Gm