change port using destination

alaios · 02-10-2005, 06:40 AM

Hi... Do u know if it is possible to change the port of some packets using iptables.? I want the decision to be based on the ip address..
Any suggestion?

fr_laz · 02-10-2005, 09:39 AM

hi,

man iptables and search for SNAT, DNAT

ex :
iptables -t nat -A POSTROUTING -s 192.168.0.3 -p tcp --sport 80 -j SNAT --to-source 10.0.0.3:8080
iptables -t nat -A PREROUTING -d 10.0.0.3 -p tcp --dport 8080 -j DNAT --to-dest 192.168.0.3:80

You can have a look at http://www.linuxsecurity.com/resourc...-tutorial.html

Bye

ugge · 02-11-2005, 09:55 AM

I you only want to change the port, then you can use the REDIRECT target.

vipspark · 03-01-2005, 04:06 AM

Hello all of you

But as u suggested to use iptables it will redirect the traffic of ftp port to another port BUT it still outer world will use the same port.

I dont know but is there any way to change the ftp port so that default ftp port will get changed.means to ftp some system user cant enter from port 21.

thanku
KeepsmilinG