When a host on a VLAN needs to communicate with a device operated at the network layer, a VLAN-based logical interface (i.e., a VLAN interface) can be created on the device. The function of the VLAN interface is the same as that of an ordinary Layer 3 physical interface, which can implement various Layer 3 features such as IPv4/IPv6 address configuration. It is used in Layer 2 transparent deployment scenarios to implement communication between VLANs.

To create a new VLAN interface, click Add on the Network > Interfaces > VLAN Interface page, as shown in the following figure.

VLAN ID: Create a virtual interface for a VLAN to achieve Layer 3 intercommunication.

Description: Briefly describe the interface.

Zone: Select the network zone to which the VLAN interface belongs.

Reverse Routing: Specify whether data packets are sent out through the same link they come in. You need to enable this option when there are WAN links of multiple ISPs; otherwise, the service may be inaccessible. This option is automatically enabled once WAN Attribute is selected.

Selecting Static IP means that the interface's IPv4 address and next-hop IP address are specified by manual configuration.

DHCP: Specify whether the IPv4/IPv6 address and next-hop IP address of the interface are automatically obtained using DHCP.

MTU in Advanced: Specify the maximum transmission unit of the interface. You can set it in the range of 68-1500.