firewall setup

[Stuart Clark]

Hi,
I am setting up my Linux FW.
I just want to get the FW box forwarding packets without anything breaking.
I have tried this a few times now but something always breaks and I have to
switch back to a system without a firewall.
Here is my diagram.

#Cisco 203.103.136.201/30#
                ^
                ^
                ^
#         Linux Firewall        #          #squid,dns10.0.0.2/25#
#203.103.136.202/30eth0#          # ssl,secondary mail10.0.0.4/25#
#       10.0.0.1/25eth1       #   < < # UT games server, ftp10.0.0.3/25#
#  203.103.136.1/25eth2  #          # mail,webserver,dns,ftp10.0.0.1/25#
                ^
                ^
#Max 6000 NAS 203.103.136.10/25# < < #Radius,SQL10.0.1.1/25#
                ^
                ^
#Modem Pool 203.103.136.20-140#

I know its a big ask, but, what iptable rules do I need on the firewall to
just get the traffic flowing?
I can experiment later

Regards

-------------------------------------
Stuart G. Clark
Manager,
Spacelink Communications Pty. Ltd.
http://www.spacelink.com.au
+61 03 9 888 9874

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