Hi!

The nameserver package is already installed and have also started the daemon (/etc/init.d/named start)..

etc/resolv.conf file show's the foll:

serach localhost
nameserver 202.63.164.17
nameserver 202.63.164.18

OK. And these are the same DNS servers you told the client machine to use?

yes... I used this DNS for the client system...

In that case either the masquerading is set up wrong or you have a firewall somewhere that blocks the traffic.

Just set up a mock ICS with two Linux machines:

MACHINE1 (the server):

MACHINE2 (the client):

The steps roughly to set it up..
Server side:

Client:

Hi,

Let's do this in a few very easy steps. First this will run on any sysV based distribution (ie Fedora, Mandrake etc)

Firs, make sure that you have uninstalled or at least disabled the firestarter or whatever other external trick you have enabled

Let the stepping begin ...

Step 1:

We configure the ip_forwarding which will let the packats "flow" from one interface to another.
In order to do this, in your favorite text editor, open the file /etc/sysctl.conf
Initially, the line looks like this


# Controls IP packet forwarding
net.ipv4.ip_forward = 0

You have to change it to

net.ipv4.ip_forward = 1

save and exit.

Now, why did we do it like this instead of just echoing in /proc/sys/net ... ? Because changin if the file in /proc, only ensures it running until the next restart. It will not work after that, because at startup, the netwqork service, via sysct, parses the file /etc/sysctl.conf, where it will read "do not enable ip_forward".

Step 2:

# service network restart
(# as in ... you have to be root)

Step 3: we add the firewall and nat rules in iptables

You arfe running on a kernel newer than 2.4 so we can safely do this:

# iptables -t nat -I POSTROUTING -s 192.168.0.1/24 -j SNAT --to-source 10.10.10.10

i didn't remember your outgoing address soi said ... 10.10.10.10 . You replace it with yours!

Step 4:
We ensure that the next time the system starts the rule will be loaded

# service iptables save

Step 5:

Double check the config of interfaces :

eth0 (the lan interface), must have no gateway set

the interfaces in the network must have as gateway, the ip of your eth0

Step 6:

The final check

from your linux based client machine (from the net 192.168.0.)
# traceroute [an external ip address]

from your windows based client machine
> tracert [an external ip address]

It is important that you check it with ip addresses
first and then with hostnames. This way we also check for name resolution failures.

Hope this is helpfull.