dhcp_release man page
dhcp_release — Release a DHCP lease on a the local dnsmasq DHCP server.
dhcp_release <interface> <address> <MAC address> <client_id>
A utility which forces the DHCP server running on this machine to release a DHCP lease.
Send a DHCPRELEASE message via the specified interface to tell the local DHCP server to delete a particular lease.
The interface argument is the interface in which a DHCP request _would_ be received if it was coming from the client, rather than being faked up here.
The address argument is a dotted-quad IP addresses and mandatory.
The MAC address is colon separated hex, and is mandatory. It may be prefixed by an address-type byte followed by -, eg
but if the address-type byte is missing it is assumed to be 1, the type for ethernet. This encoding is the one used in dnsmasq lease files.
The client-id is optional. If it is "*" then it treated as being missing.
MUST be run as root - will fail otherwise.
Only usable on IPv4 DHCP leases.
This manual page was written by Simon Kelley <firstname.lastname@example.org>.