DHCP_RELEASE(1)

✨ dhcp_release — the NAME section, bestie ✨

dhcp_release — release a DHCP lease on a the local dnsmasq DHCP server. 💅

(Yes, "on a the". We don't fix the original's typos, we respect them. Iconic behaviour, honestly.)

🎀 SYNOPSIS 🎀

dhcp_release <interface> <address> <MAC address> <client_id>

🦋 DESCRIPTION 🦋

Okay so picture this: there's a DHCP server running on your machine, and you need it to let go of a lease. That's the whole job. This little utility forces the DHCP server running on this machine to release a DHCP lease. No begging, no waiting, it just does it. 😌

What it's actually doing under the hood is sending a DHCPRELEASE message via the specified interface, which tells the local DHCP server to delete a particular lease. Boom. Gone. ✨

Now let's meet the arguments, one by one, because they all matter:

• interface — this is the interface where a DHCP request would be received if it was actually coming from the client, rather than being faked up right here. So like... you're cosplaying as the client, and this is the door they'd have walked through. 🚪
• address — a dotted-quad IP address, and it is mandatory. No address, no service. 💀
• MAC address — colon separated hex, also mandatory. It may be prefixed by an address-type byte followed by -, like this:

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

But here's the tea: if that address-type byte is missing, it's assumed to be 1, which is the type for ethernet. And this whole encoding? It's the exact one used in dnsmasq lease files. So you already know it, iykyk. 🧚

• client_id — optional, bestie! And if it's "*" then it's treated as being missing. Star means nothing. Main character energy but make it absent. ⭐

👑 NOTES 👑

MUST be run as root — will fail otherwise. 🔥

Not "should", not "preferably", MUST. If you're not root, it's giving nothing and it will fail. Periodt.

🌸 LIMITATIONS 🌸

Only usable on IPv4 DHCP leases. IPv6 girlies, this one's not for you, sorry babe. 💜

🌈 SEE ALSO 🌈

• dnsmasq(8)

💖 AUTHOR 💖

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

And that's a wrap on the General Commands Manual page for DHCP_RELEASE — the header said DHCP_RELEASE(1) and so did the footer, so you know it's official. Go forth, release some leases, and remember: root or nothing. 💅✨🎀