SMLight SLZB-06 Zigbee POE Coordinator Review

Ever since I tested and reviewed the Zigstar UZG-01, it remained in use as my primary Zigbee coordinator. I login to the web dashboard from time to time, to check for firmware updates and make sure everything is okay. Currently, it operates around 80 devices in Zigbee2MQTT without any hiccups, it’s just there and it works.

In this article, I’m testing a similar device – the SMLight SLZB-06 range of network coordinators. The SLZB-06 are also PoE/USB powered devices, compatible with both Zigbee2MQTT and ZHA in Home Assistant. SMLight also offers a Matter-ready model, the SLZB-06M, which can use Thread and operate as a border router.

Different SLZB-06 Models

Before I dive deeper, it’s crucial to differentiate between the various models in the SMLight’s SLZB-06 product range. While most are quite similar, some are well-tested and documented, whereas others, as SMLight themselves put it, are just marketing gimmicks. Here’s the official SMLight SLZB-06 product table:

The first thing you will notice is there are four different models based on Texas Instruments SoCs: SLZB-06-NO-POE, SLZB-06, SLZB-06p7, SLZB-06p10. The main difference between these chips is the amount of RAM available, with the CC2652 having 88kb or RAM while the most powerful CC2674P10 comes with 264kb or memory.

However, SMLight claims that the CC2652 barely uses 30% of memory when under full load and with a maximum number of devices paired, making the CC2652P7 and CC2674P10 obsolete. SMLight refers to these chips as a marketing gimmick and suggests going for the SLZB-06 model as its well tested and documented within the community.

When it comes to Silicon Labs SoCs, SMLight offers two models: The SLZB-06M and SLZB-06Mg24. The first model carries 96kb of memory while the latter has 256kb. The same applies here, the extra memory is not needed and is again a marketing gimmick, per SMLight.

Okay, but why shouldn’t you get the coordinator with the most RAM? Because you will be buying a more expensive device with a buggy and unestablished firmware. SMLight recommends getting the following coordinators for Zigbee or Thread networks:

• SLZB-06 (CC2652)
• AliExpress | Amazon
• SMLight Webstore

• SLZB-06M (EFR32MG21)
• AliExpress | Amazon
• SMLight Webstore

• SLZB-07 (EFR32MG21)
• Amazon | AliExpress
• SMLight Webstore

Teardown and Package Contents SLZB-06

SMLight sent me three versions of the of the SLZB-06M: The SLZB-06 (CC2652), SLZB-06p7 (CC2652p7) and SLZB-06M (EFR32MG21). All devices are neatly packed in similar boxes with the same shape but different color and branding. Each contains the coordinator, the antenna, a screw-fix helper along with some screws and, a Micro-USB to USB-C adapter.

The shape of the SLZB-06 is quite convenient for installing it anywhere you wish. You can use the screws to mount it on a wall somewhere or attach it to the frame of your network rack. It’s long and thin and doesn’t resemble a network router like the UZG-01. The antenna is as long as the coordinator, measuring at about 15cm.

Opening up the SLZB-06 requires simply prying up the backplate of the device to get to the internals. Everything is neatly laid out on the PCB, with the ethernet port positioned at the back. The USB-C port is installed on one side, somewhere at mid-length. You can power and use the SLZB-06 via PoE, USB or a hybrid between the two: powered by USB-C, connected via Ethernet.

All three SLZB-06 models are nearly identical, with the only thing different being the mesh network module. The SLZB-06 uses the Texas Instruments CC2652 [Datasheet], the SLZB-06p7 uses the [CC2652p7] and the SLZB-06M relies on the Silicon Labs EFR32MG21 [Datasheet] as the main mesh network SoC.

They rely on an ESP32-V3 [Datasheet] as their core computing module and use the CP2102N [Datasheet] as an integrated USB-to-UART bridge controller. Each model has a +20dB Amplifier paired with a 5dB antenna.

Here’s a closer photo of their Zigbee SoCs:

Home Assistant Setup SLZB-06

To test out the SLZB-06 coordinators, I’ve setup a separate Home Assistant OS Proxmox VM. I’m using and Ethernet connection to talk to the SLZB-06, which is the better way to use these coordinators. It allows me to move the coordinator to a better position and eliminate USB ports interference.

Since the CC2652 is already well-known to me, I decided to setup the CC2652p7 (SLZB-06p7) model in Home Assistant.

Web Dashboard Overview

SMLight has it’s own web dashboard that can be accessed through the IP address it gets from your router. It’s neatly organized in several categories, giving you an overview of all device features and settings menus. The current status of the SZLB-06 is displayed in the first screen, showing things like operation mode, radio mode, connected clients, network status and general device information.

The first thing to do in the dashboard is to check for firmware updates, found under the Settings and Tools menu. The great thing about the SLZB-06 coordinators is that both the Core and Zigbee firmware can be updated Over-the-air (OTA), so there’s no need to flash the device manually.

Once you click check for core updates, you will get a list of changes of the latest firmware available. Each developer version will be marked as .dev, so update only if you know what you are doing. If you unsure which version you need to flash, always go for the latest stable version (without .dev).

When you check for Zigbee updates, you will also get a list of firmware versions with a changelog. These are official Z-Stack firmware files developed by Koenkk, the main Zigbee2MQTT developer. The interesting here is that you can also flash the OpenThread firmware and use the SLZB-06p7 as a Thread border router, an experimental feature at this point.

Zigbee2MQTT Setup SLZB-06

To setup the SLZB-06 as a Zigbee coordinator with Zigbee2MQTT, open the SLZB-06 web dashboard. Select the Z2M and ZHA menu item on the left pane and copy the auto-generated code in the middle. This is automatically populated with the IP address and access port of the device.

In Home Assistant, navigate to Settings > Add-ons > Zigbee2MQTT > Configuration and paste it under Serial. If you haven’t already, populate the mqtt fields with your broker’s information and start Zigbee2MQTT. Ultimately, your configuration should look something like this:

mqtt:
  base_topic: zigbee2mqtt
  server: mqtt://core-mosquitto:1883
  user: mqtt
  password: mqtt
serial:
  port: tcp://192.168.0.27:6638
  baudrate: 115200
  adapter: zstack
  disable_led: false
advanced:
  transmit_power: 20

ZHA Setup SLZB-06

Similarly, you can setup the ZHA in Home Assistant to use the socket connection of the SLZB-06. If you are using the coordinator in Ethernet mode, you can also do this while the device is connected to Zigbee2MQTT and use them simultaneously. I talked about this use case in this article: How To Use Zigbee2MQTT and ZHA with a Single Coordinator.

In Home Assistant, navigate to Settings > Devices & Services > Add Integration > Zigbee Home Automation. Under the radio type, select ZNP and input the IP address on the next screen in the following format: socket://192.168.0.27:6638. Click submit and select Keep radio network settings to use both or Erase network settings and create a new network to setup ZHA.

Matter-over-Thread Setup SLZB-06

Besides the EFR32MG21, the CC2652 and P7 radios can also function as a Thread border router, an experimental feature of the SLZB-06 firmware. To enable this mode, click Mode in the web dashboard and toggle Matter-over-Thread. The dashboard will prompt for a firmware change, click Next followed by Change Mode.

Please note, since multi-protocol use is no longer recommended, toggling this mode will enable the SLZB-06 to be used as a Thread device only! You can revert to a Zigbee coordinator any time you need to in the web dashboard. It can also be used exclusively via an USB Connection and not Ethernet. SMLight informs me they are working on an update that would enable Thread mode over an Ethernet connection.

Once Matter-over-Thread is enabled and the firmware flashed, you can configure the SLZB-06 to operate as a Thread Network Router. SMLight made their own video of the process that you can watch here. Basically, the process involves the following:

1. Set Matter-over-Thread mode on SLZB-06/06p7/06M
2. Install Matter Add-on in Home Assistant
3. Install OpenThread Border Router router Add-on in Home Assistant
4. Open the Configuration tab and set the following
   • Device: /dev/serial/by-id/xxx…
   • Baudrate: 460800
   • Hardware flow control: off
   • Automatically flash firmware: off
   • OTBR Firewall: off
   • NAT64: off
5. Start the OpenThread Border Router Add-on
6. In Home Assistant, navigate to Settings > Devices & Services
7. Click configure to OpenThread Border Router, Thread and Matter Integrations
8. Open the Thread integration and click Configure
9. Select the three dots next to OpenThread Border Router and click Add to preferred network
10. Click the three dots again and click Use router for Android and iOS Credentials
11. Done!

VPN Setup SLZB-06

Since Zigbee coordinators are very well known to me, including SMLight models, the feature I’m most excited about is definitely the VPN connection mode. Basically, this feature allows you to form a remote Zigbee network and connect it to your Home Assistant Server at home via WireGuard!

EXAMPLE: You have a full Home Assistant server setup at home with bunch of devices and integrations. You want to setup a second Zigbee network in your office, but you do not want to deploy and run a second Home Assistant server. So, you simply setup the SLZB-06 in your office and connect it to your home HA server via WireGuard, allowing both to talk to each other over a secure tunnel. Neat, handy and very very welcome!

This process requires a Home Assistant server, a SLZB-06 coordinator setup in your remote location (2.2.6+ firmware), WireGuard Add-on and Zigbee2MQTT or ZHA. The setup is quite long and beyond the scope of the review, I intend to write a separate article detailing all the steps needed to achieve this.

Basically, it comes down to configuring the following:

1. Reserve a static IP address in your router for the SLZB-06
2. Port-forward the internal address to port 51820
   • Or use Duck DNS to expose the SLZB-06 IP address
3. Install and configure Wireguard Add-on in Home Assistant
4. Configure the VPN tunnel in SLZB-06 web dashboard
5. Configure IP routing on Home Assistant server
6. Configure Zigbee2MQTT or ZHA
7. Pair your devices

I managed to configure the VPN tunnel without any major hiccups and connect it to a separate instance of Zigbee2MQTT running as an LXC on my Proxmox server at home. If you want to try this before I write my guide, SMLight has an excellent article that you can follow along.

Final Thoughts

After using the SLZB-06 coordinator for almost a week, all I can say is, I wish these were available back in the Conbee II days. It would saved me so much trouble and made things so much easier. If you are running a Zigbee/Thread network with Home Assistant, SMLight PoE SLZB-06 are the coordinators to get.

The web dashboard makes maintenance a breeze. The core updates of the ESP32 are nothing new and have always been done Over-the-Air (OTA). The Zigbee firmware on the other hand, usually requires a flasher (via USB) or using the Home Assistant Add-on for updates. SMLight makes updates one click away, saving time and streamlining the whole process.

The most welcoming feature for me is the VPN connection mode of these Ethernet coordinators. This allows you to create a new, separate network in a second location and connect it to your server at home via WireGuard, eliminating the need to run a second server. So convenient if you have an office you want to automate or maybe install a few Zigbee smart lights in your parents house.

If you are looking for a capable Zigbee coordinator or a Thread border router to use with Home Assistant, I can comfortably recommend SMLight devices. If you don’t need PoE, they also have USB-only variants that you can use. Here are some links to their official stores:

■ Recommended ■ Second Pick ■ Experimental

• SLZB-06
• CC2652
• USB, PoE, USB/Ethernet
• Amazon | AliExpress
• SMLight Webstore

• SLZB-06p7
• CC2652p7
• USB, PoE, USB/Ethernet
• Amazon | AliExpress
• SMLight Webstore

• SLZB-06M
• EFR32MG21
• USB, PoE, USB/Ethernet
• Amazon | AliExpress
• SMLight Webstore

• SLZB-07
• EFR32MG21
• USB only
• Amazon | AliExpress
• SMLight Webstore

• SLZB-07p7
• CC2652p7
• USB only
• AliExpress
• SMLight Webstore

• SLZB-07p10 (dev)
• CC2674p10
• USB only
• SMLight Webstore

DISCLAIMER: SMLight sent me these coordinators as a testing sample for the purpose of a review. This will in no way influence, sway or affect my opinion of the device and will just be my usual observations and unbiased testing approach. I shared my guidelines and principles for collaboration with their PR person, to which they fully agreed.