I shared my internet connection by -

iptables -F
iptables -t nat -F
iptables --delete-chain
iptables --table nat --delete-chain

iptables --table nat --append POSTROUTING --out-interface ppp0 -j MASQUERADE
iptables --append FORWARD --in-interface eth0 -j ACCEPT

Where eth0 is the internet connected nic and eth1 is the LAN nic.
Internet connection sharing is working fine.

Now I want to use DNAT on my static ip and redirect all trafic on port 1433 (ms-sql-s) to 192.168.127.1

I tried the following iptables statement -

iptables -t nat -A PREROUTING --dst XXX.XXX.XXX.XXX -p tcp --dport 1433 -j DNAT --to-destination 192.168.127.1

But it is not working.

Can anyone help.

Not working as in the destination translation is'nt working or not working as in the attempt to connection from a client failed.

If the client failed to connect then you might need to open port 1434 UDP as well (not sure but found it on a website somewhere).

Thanks for your reply.

The package that access the MS SQL DB is Matrix. It is unable to connect to the database located in 192.168.127.1 while being routed through our firewall which has a static ip address.

I used the iptables statement as given above.

I might point out again that my internet connection through this static ip address which is shared through my internal lan card is working just fine.

Only when I try from outside my local area network that the sql connection error stating so and so database could not be located is encountered.

Regards