C-M-G
Series
Manual
© TDT GmbH
Chapter 5: Network Configuration
Seite 60 von 136
5.9.6 Example: Setup IP Forwarding
In the drop-down menu right of the button
Showing IPtable:
, please choose »Network address
translation (nat)« and confirm with the button.
Under »Pakets before routing (PREROUTING)« you can add a new entry with the button
Add Rule
.
Figure 20: Configuration excaple - IP Forwarding
To keep track you can add a description for an entry under »Rule comment«. Please select
Destination NAT
under »Action to take«.
Define the destination IP and the destination port under »IPs and ports for DNAT«. Please note that it is a
so-called »range«. If only one IP or one port should be forwarded, define the value range on it.
Now create conditions for the forwarding to the destination adress:
At »Incoming interface« set the the condition to
Equals
and in the second drop-down menu choose the
interface, where the originally IP paket will be received (e.g. eth1).
Indicate under »Network protocol« the required protocol (e.g. TCP)
Also set the condition Equals under „Destination TCP or UDP Port“ and indicate the port, which should be
transformed. In the upper example it is the port 55000.
Afterwards save this rule with the button
Create
and press
Apply Configuration
in the
Linux Firewall menu.
In this example all TCP pakets , which arrive at eth1 with the destination port 55000, will be forwarded to
the address 192.168.0.1 and the port 1234.
