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Install Openwrt on VNOPN Micro Firewall Appliance

·534 words·3 mins·

VNOPN device photo

I needed to replace my router, a UniFi Security Gateway, which recently died, so I purchased a VNOPN Micro Firewall Appliance to run OpenWrt. Coming from a managed Unifi device, the setup was new to me, so I’ve documented it below.

Prerequisites #

I started with these items:

My basic network layout #

My router sits behind my AT&T fiber modem, so my traffic is NAT’d since I don’t have something like an AT&T Residential Gateway Bypass setup anymore:

flowchart LR router[AT&T ARRIS router] --> VNOPN --> switch[NETGEAR switch] --> aps[Access Points]

Install OpenWrt #

Connect a USB flash drive with Ubuntu to the VNOPN appliance. (It’s probably possible to pre-load your desired OpenWrt firmware onto the USB drive, but I just download it here. Make sure an ethernet cable to your upstream modem is connected to the LAN 1 port.

Boot the VNOPN and immediately press F7 to select a boot device. Choose your USB drive and press enter:

Select boot device photo

When the installer launches, use the up arrow (↑) to navigate to the Help menu in the top right, and select Enter shell:

Ubuntu Live Installer Open Shell photo

From the terminal prompt, download an Openwrt image. I used tobiasmcnulty/router-openwrt v22.03.2 and created a Bitly link for the openwrt-22.03.2-x86-64-generic-squashfs-combined.img.gz image, to make it easier to type into the terminal. Download and decompress the image:

cd /tmp
wget -O openwrt-squashfs.img.gz
gunzip openwrt-squashfs.img.gz

Identify the internal drive you wish to install Openwrt on (in my case /dev/sda):


Write the disk image to the VNOPN internal drive:

dd if=openwrt-squashfs.img bs=1M of=/dev/sda

And reboot:


Now plug an ethernet cable from your laptop into the LAN 1 port. You should see the link become active:

Link active message in terminal photo

Configure OpenWrt #

Connect to the web UI by accessing in your browser. By default, you can log in without using a password:

Login screen

Navigate to Network→Interfaces to see the default interfaces:

Openwrt default interfaces

Next we’ll queue up a few changes:

  • My network will use NAT behind my AT&T router, which uses the 192.168.1.x DHCP range, so I want to use non-conflicting address: Edit the LAN interface and change the IPv4 address to

    Configure LAN address

  • I want LAN 1 to be the WAN port connected to my AT&T router, so edit the WAN interface and move it to the eth0 device (e.g. the LAN 1 port):

    Configure WAN interface

  • I want LAN 2 and LAN 3 to be my LAN network. Switch to the devices tab, click configure on the br-lan device, and select the eth1 and eth2 bridge ports (LAN 1 and LAN 2, respectively):

    Configure br-lan device

  • Lastly, delete WAN6 interface

Select Apply and Save. Switch your laptop ethernet cable to LAN 2 and plug your upstream ethernet cable into LAN 1.

Now you should be able to access from your browser. You should also have working Internet! If everything looks good, just plug your network switch into LAN 2 or LAN 3.