Hi, If you want to allow one ip to access one destination then you can write the below rule in iptables. iptables -t nat -A POSTROUTING -s 192.168.101.230 -d centosip -j MASQUERADE iptables -t nat -A POSTROUTING -d 192.168.101.230 -s centosip -j MASQUERADE For remianing ip you can write a simple drop rule to centos ip. This is will work you out i am sure. Regards, paps On Thu, Dec 4, 2008 at 2:51 PM, Indunil Jayasooriya <indunil75@xxxxxxxxx> wrote: > Hi, > > I know these are a few iptbales questions. NOT CentOS, anyway, I am > running a firewall on centos 5.x. > > If you can response, it would be fine. > > > I want to add a SNAT rule for one user in LAN to access one particular > destination on the internet. > > Let's say www.centos.org > > I added the below rule. But . it does NOT work > Pls assume 1.2.3.4 is the real ip of the firewall. > ip address 192.168.101.230 is the client PC > > iptables -t nat -A POSTROUTING -o eth0 -s 192.168.101.230 -j SNAT > --to-source 1.2.3.4 -d www.centos.org > > Any idea to achieve it? > > And Also, > > the below rule excludes 1 ip. it works fine. > > iptables -t nat -A PREROUTING -p tcp -m multiport -s ! 192.168.1.9 > --destination-port 80,465,995 -j DNAT --to-destination :3128 > > I want to exclude about 4 or 5 ips. > > let's say 192.168.1.11, 192.168.1.19, 192.168.1.20,192.168.1.25 > > Is there a way to do it? > > Hope to hear from you. > > > > -- > Thank you > Indunil Jayasooriya > _______________________________________________ > CentOS mailing list > CentOS@xxxxxxxxxx > http://lists.centos.org/mailman/listinfo/centos > _______________________________________________ CentOS mailing list CentOS@xxxxxxxxxx http://lists.centos.org/mailman/listinfo/centos