block all IPs except one how in my setup??
 

hello,
How to prevent my RH9 linux machine to send packets to any internal private 10.0.*.* host ips? I have one LAN in which all machines connected to switch and ther are may LANs in my Organisation. Now i want traffic from pc should only be given to an other pc in my same LAN where i know that require me crossover cable but is that possible???
In simple words, Block all IPs except one which is allowed to communicate to my pc

/sbin/iptables -I INPUT -s ! 10.0.0.1 -j DROP

change 10.0.0.1 to the ip of the machine allowed to communicate

hello,
Ok how to modify
iptables -I INPUT -s ! 10.0.0.1 -j DROP
to allow only 10.0.0.1 to have communication with me as 10.0.0.100 with condition that any other ips excluding 10.0. network? That mean if i ping 172.16.*.* and 192.168.*.* from my 10.0.0.100 its must be allowed but in 10.*.*.* range only 10.0.0.1 alllowed
How to do that?

You mean you want to only limit connect to the 10.0.0.1 host in the 10.x.x.x network, while all hosts from other networks such as 172.16.x.x/192.168.x.x are unrestricted?
ok simple, add these 2 rules on top: