Give a device the same address every time#

You will end up with a device that always gets the same address from the router's DHCP server, without configuring anything on the device itself. This is what you want for a printer, a NAS, a camera, or anything a firewall rule or a port forward names by address.

Before you start#

The operator role and a licence.
The device's MAC address, and an address for it outside the pool. An address inside the pool can be handed to something else before the reservation's owner asks for it.
A DHCP scope that already exists on that subnet.

Step 1 — Find the device#

Network → DHCP. The page shows the shared networks and subnets the configuration declares, the static reservations in each, and the live lease table — and it cross-links between them, so the fastest way to make a reservation is from the lease the device already has.

Step 2 — Add the reservation#

+ Add reservation. Choose the subnet, name the mapping, and give the address and MAC.

set service dhcp-server shared-network-name LAN subnet 192.0.2.0/24 static-mapping printer ip-address 192.0.2.10
set service dhcp-server shared-network-name LAN subnet 192.0.2.0/24 static-mapping printer mac 00:00:5e:00:53:01

The name is the mapping's identifier in the configuration. VyOS accepts letters, digits and hyphens; keep it recognisable, because it is what you will see in a diff two years from now.

To change an existing one, open its row: the panel shows the current values and stages only what you edit.

Step 3 — Make the device ask again#

A reservation does not take a lease away from a device that already has one. Either wait for the lease to expire, or make the client renew — unplug and replug, or release and renew on the device.

Check it worked#

The lease table shows the new address. Network → DHCP, the live lease rows.

bash

show dhcp server leases

And the device is where you expect it:

bash

ping -c 3 192.0.2.10

What you cannot do per reservation#

Undoing it#

delete service dhcp-server shared-network-name LAN subnet 192.0.2.0/24 static-mapping printer

The reservation panel's Delete reservation stages exactly that. The device keeps its current lease until it expires.