Unifi Layer 3 Adoption

Posted Aug 14, 2022 Updated May 24, 2023

By Karubits 3 min read

Adoption Methods

There are three options for adopting devices over different networks.

DNS
Using DHCP options
Manual configuration

DNS

If you have a internal DNS server that you manage you can simply add a dns A record for unifi pointing to the IP address of your unif controller. As soon as Unifi devices it will begin trying to resolve unifi and if successful it will connect to the Unifi Network Controller.

DHCP Adoption

Unifi uses option 43 vendor-specifc to specify the Unifi Controller IP address.

pfsense

Pfsense ues hex code format to specify the unifi controller ip address. To concert an IP address to hex you can use the gethostip command from the syslinux-utils packge in Debain/Ubuntu.

Convert the IP to hex

  
sudo apt install -y syslinux-utils
gethostip -x 192.168.46.250
C0A82EFA

Then append the suboption of 01 and payload lengh of 04 in front of the hex output. The final result would be be 01:04:C0:A8:2E:FA
Log into pfsense ➡️ Services ➡️ DHCP Server and scroll down to the bottom of the page to “Other Options” ➡️ Addational BOOTP/DHCP Options. And add the option 43 hex string as pictured below: PFsense DHCP Option for Unifi L3 Adoption

isc-dhcp-server

In the /etc/dhcp/dhcpd.conf you will first need to define vendor dhcp option for Unifi.

  
option space ubnt;
option ubnt.unifi-address code 1 = ip-address;
class "ubnt" {
        match if substring (option vendor-class-identifier, 0, 4) = "ubnt";
        option vendor-class-identifier "ubnt";
        vendor-option-space ubnt;
}

Then in your scope you can simplly put the IP address of the Unifi Network Controller.

  
subnet 192.168.50.0 netmask 255.255.255.0 {
        option domain-name-servers 1.1.1.1, 8.8.8.8;
        option routers 192.168.50.1;
        option ubnt.unifi-address 192.168.46.250;  ##<----- Unifi Controller IP Address
        pool {
            range 192.168.50.50 192.168.50.250;
        }
}

Be sure to restart the dhcp server for the changes to take effect. systemctl restart isc-dhcp-server

Windows Server DHCP

On the DHCP Server open a Powershell Terminal (As an administrator).

  
$UNIFI_CONTROLLER_IP = "172.16.1.4"
$SCOPE = "192.168.4.0" 
   
# Create the vendor class
Add-DhcpServerv4Class -Name Ubiquiti `-data "ubnt" -Type "Vendor"
   
# Create a new DHCP option under the vendor class 
Add-DhcpServerv4OptionDefinition -Name "UniFi Controller" -OptionId 1 -Type "BinaryData" -VendorClass "Ubiquiti" -Description "Unifi Controller IP as Hex Object"
   
# Convert the controller IP into command separated hex in the expected format.
$ip = "$UNIFI_CONTROLLER_IP"
$octets = $ip.Split(".")
$hexOctets = @()
foreach ($octet in $octets) {
    $hexOctets += "0x{0:X2}" -f [int]$octet
}
$hexOctets -join ", "
   
# Add the controller IP option to the targeted scope
Get-DhcpServerv4Scope $SCOPE | Set-DhcpServerv4OptionValue -VendorClass 'Ubiquiti' -OptionId 001 -Value $hexOctets

Manual Adoption (SSH)

Connect the Unifi device to the network
Locate the IP address of the device and SSH into the device. The default user is ubnt and password is ubnt.

Then set the inform URL to the hostname or IP address of your Unifi Network Controller.

# Example of setting the inform URL with a FQDN
set-inform http://unifi.karubuts.com:8080/inform
# Example of setting the inform URL with an IP address. 
set-inform http://192.168.46.250:8080/inform

To confirm the inform URL has been set simple type info in the command prompt.

USW-Pro-48-PoE.6.2.14# info
Model:       USW-Pro-48-PoE
-
Version:     6.2.14.13855
MAC Address: 24:7a:4c:89:6a:1b
IP Address:  192.168.20.10
Hostname:    USW-Pro-48-PoE
Uptime:      6509224 seconds
-
Status:      Connected (http://unifi.karubuts.com:8080/inform)

The device should be now visable in the Unifi Network Controller dashboard.

References

network, unifi

This post is licensed under CC BY 4.0 by the author.