DHCP\_RELEASE(1) General Commands Manual DHCP\_RELEASE(1)

# [NAME](#NAME)

dhcp\_release - Release a DHCP lease on a the local dnsmasq DHCP server.

# [SYNOPSIS](#SYNOPSIS)

**dhcp\_release <interface> <address> <MAC address> <client\_id>**

# [DESCRIPTION](#DESCRIPTION)

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

10-11:22:33:44:55:66

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.

# [NOTES](#NOTES)

MUST be run as root - will fail otherwise.

# [LIMITATIONS](#LIMITATIONS)

Only usable on IPv4 DHCP leases.

# [SEE ALSO](#SEE_ALSO)

[**dnsmasq**(8)](/man/os/dnsmasq/dnsmasq.8)

# [AUTHOR](#AUTHOR)

This manual page was written by Simon Kelley <simon@thekelleys.org.uk>.

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Document: dhcp_release(1) from dnsmasq 2.93-r2 (Chainguard OS)
Source: https://thekelleys.org.uk/git/dnsmasq.git