Overview
Readers will learn how to assign a fixed IP address to clients using DHCP on the UDM and USG models.
- Applicable to the latest firmware on the UDM and USG models.
- More information on DHCP can be found in the Intro to Networking - Dynamic Host Configuration Protocol (DHCP) article.
Table of Contents
- Introduction
- Assigning a Fixed IP Address to a Client Device
- Assigning a Static or Fixed IP Address to a UniFi Device
- Related Articles
Introduction
Fixed IP addresses assigned via DHCP are a way to ensure that the client device will use the same IP address. Another name for a fixed IP address is a static IP mapping or DHCP reservation. This feature is especially useful when a client on the LAN needs to be reachable on a particular address, for example when forwarding a port to the device.
Fixed IP addresses allow you to control these IP address assignments using the DHCP server that is running on the UDM/USG. The advantage of this method is that the client configuration does not need to be altered and they can keep using DHCP instead of manually configuring a static IP address on the client. The fixed IP address is configured per network and must not overlap with other assigned addresses.
Assigning a Fixed IP Address to a Client Device
Follow the steps below to assign the fixed IP address on the UDM/USG, depending on whether the client is known or not.
Known ClientA client that has previously connected to the network and is listed in the
Insights > Client History section.Unknown ClientA client that has never connected to the network.
1. Navigate to the 
Clients section and select the client to open the properties.
2. Select the Config tab and expand the Network section.
3. Select Use fixed IP address and enter the necessary information. For example:
Network: LAN
IP Address: 192.168.1.100
3. Save the settings.
4. The change will not be applied automatically as the client will still be using the previously assigned DHCP address.
5. Optionally restart the client or renew the DHCP lease manually to force it to obtain the new IP address:
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Open a Command Shell (CMD) or PowerShell window and run the following command: ipconfig /renew
ipconfig /all
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Navigate to the advanced network settings for the network adapter: |
Windows Client
macOS client6. Clients that are assigned a fixed IP address will be displayed in the Insights > Client History > Fixed IP section.
1. Navigate to the Clients section and select the Add Client option.
2. Enter the necessary information. For example:
MAC Address: <client MAC address>
Alias: <client name>
User Group: Default
Fixed IP: Checked
Network: LAN
IP Address: 192.168.1.100
3. Save the settings and apply them.
4. Connect the client device to the network.
5. Clients that are assigned a fixed IP address will be displayed in the Insights > Client History > Fixed IP section.
Assigning a Static or Fixed IP Address to a UniFi Device
Fixed IP addresses can be assigned to UniFi devices while they are still unknown (unadopted), and the process followed is the same as the one described in the Unknown Client Fixed IP steps from the section above.
Adopted UniFi devices can be configured with a static IP address (not relying on DHCP) by changing the network settings from DHCP to a statically assigned address:
1. Navigate to the 
Devices section and select the UniFi device.
2. Select the Config tab and expand the Network section.
3. Change the Configure IP option from Using DHCP to Static IP and enter the necessary information. For example:
IP Address: 192.168.1.5
Subnet Mask: 255.255.255.0
Gateway: 192.168.1.1
Preferred DNS: 192.168.1.1
Alternate DNS: Optional
DNS Suffix: Optional
4. Queue the changes.
Related Articles
Intro to Networking - Dynamic Host Configuration Protocol (DHCP)