Using Luci to set up VLAN on a router in bridge mode

Installing and Using OpenWrt Network and Wireless Configuration
1

Is this possible?

I have my AT&T router in IP passthrough mode. My Flint 2 router now has the public IP address and handles all home networking.

I have a Flint 1 router connected to the main router in AP/bridge mode via an Ethernet cable from a LAN port on the Flint 2, therefore all clients connecting to the switch via Ethernet will be on the main network.

I am essentially trying to use one of the ports on the Flint 1 and have it be a VLAN on a different subnet. Is this possible with the Flint 1 being downstream of the Flint 2? Can the Flint 1 not be behind the Flint 2 and use one of its ports as a VLAN port with internet access while in bridge mode?

Here is my network topology:

topology
topology1002×1674 40.6 KB

2

Welcome!

A picture of what you're trying to achieve might help if things are not clear from words.

If your router is running GL.iNet firmware, it may or may not behave the way an OpenWrt install would, as many of their models use custom kernels and drivers.

To create and use a VLAN, you generally need to:

  • Create a device for the VLAN on a physical interface attached to the CPU
  • Create an interface that encapsulates the device
  • Create bridge device and interface that covers the interface and the WiFi interfaces (if any) you want associated with it
  • Modify the switch as needed so that
    • The VLAN is known by the switch
    • The CPU gets the VLAN tagged
    • The hardwire link to the upstream router gets the VLAN tagged
    • Any other switch ports are tagged or untagged as your application needs

You'll typically need to create and/or adjust firewall zones as well.

The abstraction layers are:

  • Device -- kernel level -- like eth0.1234
  • Interface -- OpenWrt configuration level -- set protocol, addresses, ... here
  • Firewall zone -- Logical level above interface
3

Hi Jeff,

I have added my network topology to the first post.

So if I'm understanding what you're saying correctly, let's imagine that the CPU port is eth0 and the port I want to use as a VLAN is eth1.

Within Luci under Network > Devices, there is already a network device set up for both eth0 and eth1. I also have a VLAN device set up on eth1 as eth1.20.

In Network > Interfaces, am I supposed to create a bridge including eth0, eth1 and eth1.20 all in one?

Forgive me if I'm missing something, just trying to get my head wrapped around the situation.

4

Are these devices running official OpenWrt, or the GL-inet stock firmware?

5

Hi psherman, you are correct. They are running the stock firmware with Luci.

6

If this is the case, you need to ask in the GL-inet forums because the gl-inet forks are significantly modified relative to the official OpenWrt firmware. Those differences can be material in terms of how to implement VLANs and the like, as the syntax found in their firmware is not valid in official OpenWrt.

Alternatively, you can install the official OpenWrt firmware if your specific devices are supported.

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