CheckPoint firewall behind DSL router

Dear all,

Can anyone enlighten me on this? I'm trying to set-up a service (ftp for
example) running on a PC (IP:192.168.0.100) behind a CheckPoint R55 firewall
that is behind a DSL router (LinkSys) to be accessible from internet static
IP. I think I am having trouble with NAT between the router and firewall as
the packets don't even show up in the firewalll log. If I connect router to
the ftp server directly (with port forwarding) it works fine:
(Internet) ---Public IP(LinkSys Router)192.168.0.2---(fwd port 20 to
192.168.0.100:20)---192.168.0.100(FTP server)
The above only works if the ftp server has default gateway and DNS set to
192.168.0.2

What I want to achieve is this:
(Internet) ---Public_IP(LinkSys Router)172.16.1.2---(fwd port 20 to
172.16.1.100:20)---172.16.1.1(Firewall)192.168.0----192.168.0.100(FTP
server) with default gateway and DNS set to 192.168.0.2

Problem appears to be in NAT-ing 172.16.1.100 to 192.168.0.100 and NAT-ing
192.168.0.2 to 172.16.1.2

Here is what I tried:
Original packet:
    Source: 172.16.1.2
    Dest: 172.16.1.100
    Service: ftp-pasv

Translated packet:
    Source: original
    Dest: 192.168.0.100
    Service: original
--------------------
Original packet:
    Source: 192.168.0.100
    Dest: 192.168.0.2
    Service: Any

Translated packet:
    Source: original
    Dest: 172.16.1.2
    Service: original

What am I doing wrong?

Thanks,

Dave
Received on Thu Sep 29 19:57:08 2005