In this section we will go over how to set up a VLAN interface
Navigate to Connections tab under the Network heading in the GUI. You will see an Add button to drop down and create a New VLAN. (Note FSN devices are preconfigured with one device already set up as eth0.103)
In this scenario we've created a new one
Select the relevant VLAN physical interface, below we've selected lan1 as this is our primary breakout interface.
Choose an appropriate VLAN ID, IP address and Netmask
The rest of the options are left default as shown below
In order for phones to receive DHCP from this address we open up the subnet to serve DHCP as shown below
Enable DHCP Server by checking the box, and open a range for the selected IP address.
In this case we've inputted the DHCP Router Address which is not necessary but handy for external handsets to negotiate this interface.
Accept and Review / Apply the changes.