4 minute read

To protect my TrueNas Scale installation from power outage, I bought a UPS. I had a good deal on Huawei UPS2000G, and considering that it’s an online UPS it was a no-brainer for me. However, with all it’s advantages, it has some drawbacks:

  • Pretty loud fans, which doesn’t make it a good fit for home
  • Limited support by NUT

Network UPS Tools and limited support in my case means that I had to compile drivers and nut-server.

Overall, always check Hardware compatibility list before buying UPS.

Anyway, I’ve managed it to work, but this was not an easy task. TrueNas Scale documentation is sparse and in some way misleading.

In this post I’ll show how you can compile drivers and connect your UPS to TrueNas Scale.

Huge shout out to this blog post which helped me a lot. It’s in Chinese, but with google translate this is not an issue.

Connecting UPS to the TrueNas Scale

That’s the easiest part. Just connect UPS to the USB and make sure that it’s visible in the logs:

root@truenas ~# dmesg | grep converter
[    6.196754] xr_serial 7-1:1.0: xr_serial converter detected
[    6.202646] usb 7-1: xr_serial converter now attached to ttyUSB0

As you can see, my UPS2000G is now connected to the ttyUSB0 port and can be accessed via /dev/ttyUSB0. We will use this information later.

Compiling NUT driver from source

As I already mentioned, even though NUT supports Huawei UPS2000G, it’s driver is not enabled by default. You have to compile NUT with those driver enabled. To do this:

  1. Install Truetool, which is a collection of useful bash scripts for the TrueNas Scale.

  2. Enable apt using Truetool
    ./truetool --apt-enable
  3. Install dependencies
    apt install nut-modbus libmodbus-dev libusb-dev
  4. Clone NUT git repo
    git clone https://github.com/networkupstools/nut.git --depth=1
    cd nut
  5. Run autogen to generate files

Please notice that in my TrueNas Scale version Bluefin-BETA kernel 5.15.62 required tools(AutoConf,etc) were already installed. You might need to install them.


After successfull generation, you should see configure and Makefile:

root@truenas ~/g/nut (master) [1]# ls -ld configure
-rwxr-xr-x 1 root root 1276481 Nov 14 09:58 configure*
root@truenas ~/g/nut (master) [127]# ls -ld Makefile
-rw-r--r-- 1 root root 50881 Nov 14 10:49 Makefile
  1. Configure compilation options

Since TrueNas Scale uses Debian under the hood, we need to use Debian paths for config/systemd files:

./configure --with-modbus \
    --with-user=nut --with-group=nut \
    --datadir=/usr/share/nut \
    --sysconfdir=/etc/nut \
    --includedir=/usr/include \
    --with-statepath=/run/nut \
    --with-pidpath=/run/nut \
    --with-altpidpath=/run/nut \
    --with-drvpath=/lib/nut \
    --with-udev-dir=/lib/udev \
    --with-systemdsystemunitdir=/lib/systemd/system \
  1. Compile huawei-ups2000 driver

We don’t need to compile all the NUT components, we’ll just compile the driver:

cd include
cd ../common/
cd ../drivers/
cd drivers
make huawei-ups2000
  1. Copy compiled driver to the /lib/nut/ The idea here is that we will use NUT installed by the system, and just add our driver there:
    cp huawei-ups2000 /lib/nut

Make new driver visible to the TrueNas

List of supported by NUT UPSes are kept the /usr/share/nut/driver.list.

Normally, you would just copy generated during compilation list to /usr/share/nut/driver. But unfortunately, this will not make Huawei UPS2000G visible to the TrueNas Scale. I’ve spend couple hours trying to understand why it’s not working and as it turns out, TrueNas Middleware has RegExp which doesn’t match our entry.

So to fix this, just add a slightly modified entry to /usr/share/nut/driver:

"Huawei"        "ups"   "3"     "UPS2000-G and UPS2000-A series"        ""      "huawei-ups2000"

And restart TrueNas Scale middleware:

systemctl restart middlewared

After restart, you should see Huawei UPS2000G in the System Settings->Services->UPS

Screenshot 2022-11-15 at 11 35 16

Configure UPS service

We want to configure our UPS through the web interface. This way, TrueNas Scale will generate all the NUT config files for us. Go to the System Settings->Services->UPS, and pick:

  • driver - Huawei ups 3 UPS2000-G and UPS2000-A series MODBUS (USB with Linux 5.12+, or Serial RS-232) (huawei-ups2000)
  • port - /dev/ttyUSB0
  • User - nut

For me, setting port to /dev/ttyUSB0 didn’t work through the web interface, so I had to do it in the CLI:

midclt call ups.update '{"port": "/dev/ttyUSB0"}'

If everything configured correctly, you can save the settings and start UPS service.

Checking that UPS is connected properly

To check that your UPS is visible by the TrueNas and is working properly:

  • Check that NUT services are up and running:
    systemctl status nut-server nut-client nut-driver
  • Check out which port is used by the UPSD service: UPSD is responsible for serving the data from the drivers to the clients. It connects to each driver and maintains a local cache of the current state. Config for the UPSD is generated by the TrueNas Scale middleware. For me, UPSD listens on the port 3494:
    cat /etc/nut/upsd.conf
    LISTEN 3494
    LISTEN ::1 3494
  • Connect to UPS UPSC is provided as a quick way to poll the status of a UPS server. Make sure that you’re using correct port:
    root@truenas ~/g/n/common (master)# upsc ups@
    Init SSL without certificate database
    battery.capacity: 9
    battery.charge: 100.0
    battery.charger.status: charging
    battery.packs: 2
    battery.runtime: 27000
    battery.voltage: 27.3
    device.mfr: Huawei
    device.model: UPS2000G
    device.serial: 2102290606HGMA001171
    device.type: ups
    driver.name: huawei-ups2000
    driver.parameter.pollinterval: 2
    driver.parameter.port: /dev/ttyUSB0
    driver.parameter.synchronous: auto
    driver.version: 2.8.0-Windows-86-ga43b966ba
    driver.version.internal: 0.03
    input.bypass.frequency: 50.0
    input.bypass.voltage: 237.1
    input.frequency: 50.0
    input.voltage: 237.1
    output.current: 0.0
    output.frequency: 50.0
    output.power: 100.0
    output.realpower: 0.0
    output.voltage: 237.1
    ups.beeper.status: enabled
    ups.delay.reboot: 60
    ups.delay.shutdown: 60
    ups.delay.start: 60
    ups.firmware: V2R1C1SPC50
    ups.firmware.aux: P1.0-D1.0
    ups.load: 17.0
    ups.mfr: Huawei
    ups.model: UPS2000G
    ups.power.nominal: 1000
    ups.serial: 2102290606HGMA001171
    ups.status: OL ECO CHRG
    ups.temperature: 27.2
    ups.timer.reboot: -1
    ups.timer.shutdown: -1
    ups.timer.start: -1
    ups.type: online

Now, when the power goes out, you will receive alerts in the UI:

Screenshot 2022-11-15 at 11 55 52

Or via email(if configured):

Screenshot 2022-11-15 at 11 57 48