Explicitly frees up assigned IP addresses. You can use this command to manually free up addresses previously assigned to DHCP hosts.
setdhcpfree -a start_IP_address [-n number_of_addresses]
setdhcpfree -a 205.15.3.10 -n 5
This command will free up five addresses starting with 205.15.3.10. These addresses will be available for reassignment to hosts configured for DHCP.