I have a proxy server, what i want is that the IP address assigned to the server cannot be chosen by anybody else in case the server goes down, how can i accomplish that. In case that the server goes down becaue of power and some client chooses the IP address of the server, so that when the server is up again it ain't functional. How could this situation be avoided. Moreover if the server also runs a dhcpd, how could the daemon be configured so that the clients who get IP addresses asigned through the DHCP are able to access the Internet otherwise if someone chooses the address manually, the Internet should not be accessible. The server may act as a proxy server or gateway to the Internet. Thanks

You cannot prevent someone from attempting to take an ip address, if the router is down it cannot do anything to stop that from happening.

However I have seen windows choke when someone tried to do that, the OS was toasted and had to be reinstalled. Linux would not have that problem.


You can use MAC address filtering with squid. That's not fool proof either, but it takes a lot more than hijacking an ip address.

The only thing to do would be to have every connection routed to a secure login page before allowing access to the internet if that's what your trying to do.