rootninja

It’s possible you have multiple dhcp servers on the same segment and you just want them to leave each others hosts alone. In this case you don’t want the first server that responds to a new machine on the network asking for a lease with a DHCPNAK! This will really hose most windows machines because they will stop asking right away while the user has no idea what happened.

ignore unknown-clients;

Oh hey, would you look at that. It’s right there in the man page. I’ll just go and ignore my unknown-clients and my server will be happy right?

Straight from the man page – the ignore unknown-clients statement explicitly does _not_ do what 90% of everyone in the world wants it to do, and that is IGNORE unknown clients.

The unknown-clients flag is used to tell dhcpd whether or not to dynam-
ically assign addresses to unknown clients. Dynamic address assign-
ment to unknown clients is allowed by default. An unknown client is
simply a client that has no host declaration.

The use of this option is now deprecated. If you are trying to
restrict access on your network to known clients, you should use deny
unknown-clients; inside of your address pool, as described under the
heading ALLOW AND DENY WITHIN POOL DECLARATIONS.

dhcp.c I hate you.

if (!packet -> shared_network) {
	log_info ("Packet from unknown subnet: %s",
	      inet_ntoa (packet -> raw -> giaddr));
	goto out;
}

But I really don’t want to have to hack the code just for this. Maybe the best way around this is to reduce the logging level elsewhere. All I ask is that dhcpd stfu about the other hosts on my network! If I didn’t define then, then I don’t care about them. Leave me alone!