DNS server problem

[Rahul Garg]

Well, the detailed  description of the problem is  :   I want to make my linux m/c  a linux server (intranet).I have made it a DNS server(internal).and file server(Samba) I have configured a modem on linux server. when i connect to internet it appends two lines to /etc/resolv.conf nameserver  ipaddress  nameserver ip address and it removes ipaddress of internal dns server. #These ip addressses comes same everytime i connect to internet.I have not provided these ip addresses anywhere. moreover the default gateway which is set to linux server also changes which i think is dynamicaly provided and can be seen thru /sbin/route.   and when i ping google.com it pings even when my   DNS server  ' named' daemon is not running. what i want is when i ping it should look for local dns server to resolve the ip address and if not resolved it should look the named.conf file where the    forwarders{ipaddress;}; option is provided. It should not be able to ping if named daemon is not running. also, if i want to make my linux m/c as gateway server  i think i have to make forwardipv4 option to yes in /etc/sysconfig/network file.an gateway option as ipaddress of the linux m/c..Is this enough to make it the gateway server without any firewalls which i would it after sometime. on client m/c what i want is my client window m/cs connected to linux server should be able to connect to internet thru linux server. on client m/cs i have provided the gatewayand dns server as the ipaddress of linux server.i am able to ping local m/cs thru client m/cs but not the internet.     Any suggestions will be helpful.   Thanks, Rahul