IPtables router specific IP internally to another internal IP

[Illinois]

Please help me in this following issue. I am trying to route an Internal IP address on another internal IP address. The router which I am using is having 2 NIC's. One NIC is internal (192.168.1.xxx) and other is an external NIC (24.xxx.xxx.xxx). I know that this could be achieved by use of IPtable commands but I dont know which commands will do the trick. Therefore if anybody of you knows how to IPtables router specific IP internally to another internal IP then please share some information. Thanks in advance.

[Milton.J]

The routing engine which will be used has to know all the REAL addresses to complete the tasks. To know the real source of the packer during final communication, the source NAT needs to be done POST. While to know the actual destination of the packet, the destination NAT has to be done PRE. Following the steps above will help you in achieving your task using IPtables.

[Spyrus]

Using the following command in the IPtables will help you route one Internal ip address on the other internal IP address.

iptables -t nat -I PREROUTING -s webbrowser -d (destination IP) --dport 80 -j DNAT --to-destination myserver:80

Enter the following command and see if it works. For making the command work, you will have to replace the Destination IP block with the IP which you want to re-route. Rest of the syntax and the command is same.

[Illinois]

As suggested I entered the command suggested by you but the command is not working. Whenever the command is entered in the IP tables, it gives and error saying "-dport is an unknown argument". I cant figure out what is causing such problem and hence need your help in solving the issue. Please help.

[Spyrus]

There must be some problem with the version of the IPtables which you are using. Either the version is outdated or the version is not installed properly. There are many files associated to any of the application which is installed on the computer. If any of the file which is associated to the application is not working then the application will not work properly. Hence I would suggest that you remove the current installed version of IP tables and download latest version. Install the application and then check if the same error is achieved or not.

[Illinois]

Thanks for helping out, the solution really helped in routing the one internal IP address on the other internal IP address. The problem was with the version of IP tables which I was using. The version was outdated which created problems while using the application. After updating the version, now there is no issue.

[Spyrus]

I am glad that the solution worked for you. I also had faced similar problems with IP tables earlier and updating the version of IPtables had worked hence I suggested you to try to update the version of IP tables. Although if there are any problems with IP tables then let us know.