RE: problems converting iptables script from eth2 ....

[Santi <nagajuna@xxxxxxxxxxxxxxxx>]

You mean you don't get any access to the Internet from any
machines on your private network and / or from the firwall machine
itself?
I have the same mysterious problems until I tweaked these:

# Flushing pre-existing rules:
iptables --flush INPUT
iptables --flush OUTPUT
iptables --flush FORWARD
iptables -t nat --flush
iptables -t mangle --flush

# Policies
# Set the default policy:
iptables --policy INPUT ACCEPT
iptables --policy OUTPUT ACCEPT
iptables --policy FORWARD DROP

# This rule affects LAN access to the Internet.
# If DROPped access is denied.
iptables -t nat --policy PREROUTING ACCEPT

# This rule affects the localhost:
iptables -t nat --policy OUTPUT ACCEPT

# Specifies source changes to outgoing packets routed
# through the box (SourceNAT, MASQUERADE). Somehow,
# setting this to DROP denies access to X-server.
iptables -t nat --policy POSTROUTING ACCEPT

# This rule affects packets originating from the LAN
# and is destined for the Internet:
iptables -t mangle --policy PREROUTING ACCEPT

# This rule affects Internet access for the host machine
# and pings originating from the LAN: if set to drop then access is		# 
denied!
# A drop policy does not affect LAN access to the Internet.
iptables -t mangle --policy OUTPUT ACCEPT

I don't know what the problem is the above settings restored my services 
again when I had a similar settup to yours.  Right now I'm rewritting 
FORWARD rules for eth0/eth1 pairing, INPUT/OUTPUT rules for 
eth0(Internet connected) as well as INPUT/OUTPUT rules for eth1 (private 
LAN connected).  My new rules may mean that I will be able to set the 
aforementioned rules to DROP.


Maybe this helps you a bit in some way.