Exclude a mac Address in Dhcp server
 

How could I exclude a mac address in Dhcp server so that the special client could not assigned ip address?

how are you assigning your ips? router server and what are you using to assign your ips?

I assign ips by configuring Dhcp.conf

host smallfry {
hardware ethernet 08:00:2b:4c:59:23;
fixed-address 192.168.1.222;
}

you might just be able to set this to 0.0.0.0 or something outside your range