topic Re: Linux firewall query in Operating System - Linux

Linux firewall query

dhananjay_1 — Mon, 11 Jul 2005 22:55:16 GMT

Hello !
We have a win2k cluter setup which current IP's are as followos
Node1-10.30.X.196
Node2-10.30.X.197
Cluster ip- 10.30.x.198
we are going to change this ip's as we want to put a Linux firewall .
After putting this firewall the Win2k Server ip will be like this
Node1-172.168.x.6
Node2-172.168.x.7
Cluster ip- 172.168.x.8
Hence we want to NAT this ip's (one to one ) in linux firewall .
172.168.X.6 --- 10.30.X.196
172.168.x.7 --- 10.30.x.197
172.168.x.8 --- 10.30.x.198

Also we want to open 1414 and 1419 port on linux firewall(Bidirectonal)for IBM webSphere MQ -channel.

Can any body help me in this ,

Regds
Dhananjay

Re: Linux firewall query

Stuart Browne — Mon, 11 Jul 2005 23:07:07 GMT

A pair of rules, one for inbound, one for outbound:

iptables -t nat -I PREROUTING -d 10.30.x.198 -j DNAT --to 172.168.x.8
iptables -t nat -I POSTROUTING -s 172.168.x.8 -j SNAT --to 10.30.x.198

This translates the packets coming in, destined for 10.30.x.198 to be redirected to 172.168.x.8, and the packets coming out of 172.168.x.8 changed to look like they came from 10.30.x.198.

You'll have to make sure that the routing tables are good.

Re: Linux firewall query

dhananjay_1 — Tue, 12 Jul 2005 22:46:05 GMT

thanks ...

I want to add 1419 port in linux fw which is not there in /etc/services file .

Can any one help how to do this ....