I bought a CyberPower CP1500PFCLCD UPS for my new built NAS. I didn’t get the optional RMCARD205 card which is at the time of this writing cost $160 on Amazon. I could get a new UPS with that price, so I opted out and sticking with the USB option.
Now, as the title says, I am going to be using the Network UPS Tool (NUT) to keep tabs of my UPS and notify me via email when an event occurred. I have a Raspberry 3B that is laying around and want to make good use out of it.
This post assumes that you already have the following:
- A spare Raspberry Pi 3B(+) or 4B
- A UPS with a USB
- MSMTP installed (for notification)
In Figure 1, I am only going to be working on the NAS Nut Client and the RPi NUT Server. The drawing shows the physical layout. The servers are connected to the UPSes and they are connected the NUT server via the network LAN. If there is a firewall between the NUT server and NUT clients, make sure to allow the port 3493/tcp.
Installing the NUT software will complain that the service failed to start. This is normal. The NUT needs to be configured first before we can start the service. The error that I am talking about is below.
nut-monitor.service: Can't open PID file /run/nut/upsmon.pid (yet?) after start: No such file or directory nut-monitor.service: Failed with result 'protocol'. Failed to start Network UPS Tools - power device monitor and shutdown controller.
Install the NUT software via the
sudo apt install nut nut-server nut-client
Plug the USB cable from the UPS to the Raspberry Pi. Make sure that the RPi can see the UPS. In my case it is the USB with an ID of
0764:0601. The value 0764 is the vendor ID and the 0601 is the product ID.
[email protected]:~ $ lsusb Bus 001 Device 004: ID 0764:0601 Cyber Power System, Inc. PR1500LCDRT2U UPS Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp. SMSC9512/9514 Fast Ethernet Adapter Bus 001 Device 002: ID 0424:9514 Standard Microsystems Corp. SMC9514 Hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
At this point, we will be editing several files
nut.conf. These files are all located in
usp.conf– this is where to specify the driver to use per UPS
uspd.conf– this file where we instruct nut what IP and port to listen to
uspd.users– this file contains the nut user credentials and their access level
upsmon.conf– this contains information about monitoring
nut.conf– this file is where we set the mode of the RPi
To locate the driver to use, you can find them here https://networkupstools.org/stable-hcl.html
If you have multiple UPS’es, in the file
ups.conf, each UPS must have its name block defined. To distinguish a UPS from the other UPS, the options
procductid options is needed . The
port for the driver
usbhid-ups will always be set to
man usbhid-ups for more info.
Make sure that every parameter is correctly entered otherwise, you might get the error. The safest way is to add the driver and port first as shown in
[ups2]. In addition, if you are using Cyberpower UPS like I do, you will need to add the
pollinterval. The reason being, after a few minutes you will get a Data stale error. Here is the discussion about it.
# Error for having a wrong value in the serial number. Poll UPS [[email protected]] failed - Driver not connected
[ups1] driver = usbhid-ups port = auto desc = "CyberPowerPC PR1500LCDRT2U" serial = CXXKU1234567 vendorid = 0764 productid = 0601 pollinterval = 15 [ups2] driver = usbhid-ups port = auto
Let’s configure the
upsd.conf file. We have to specify the listening addresses and port(s). If you have a firewall installed, make sure to allowed inbound to port 3493/tcp.
echo "LISTEN 127.0.0.1 3493" >> /etc/nut/upsd.conf echo "LISTEN 10.0.7.42 3493" >> /etc/nut/upsd.conf
Let’s create the nut credentials on the
uspd.users file. These credentials will be used to access the daemon. The nut clients will be using the user
upsmon_remote credentials. The difference between the upsmon master and slave is that the master is the last one will get shutdown when power failed. This is the reason why I didn’t use a VM to be a NUT server.
sudo cat >> /etc/nut/upsd.users << EOF [upsmon_master] password = s3cR3tpa$5w0rd actions = SET instcmds = ALL upsmon master [upsmon_remote] password = s3cR3tpa$5w0rd upsmon slave EOF
We need to configure the
upsmon.conf. We need to add at the bottom of the
upsmon.conf the user. For multiple UPS, make sure to add another line for the other MONITOR.
echo "MONITOR [email protected] 1 upsmon_master s3cR3tpa$5w0rd master" >> /etc/nut/upsmon.conf
The last part is to change the mode from
netserver in the
sed -i 's/MODE=none/MODE=netserver/' /etc/nut/nut.conf
To check the status of the UPS you can use the command
upsc <ups-name-in-ups.conf>. From here you can grab the serial number and add it to the ups.conf block.
For the UPS that is not the first one, if you run the
sudo upsc ups2, you will get an error. This fix this issue reboot the RPi.
[email protected]:/etc/nut $ sudo upsc ups1 sudo: unable to resolve host nut-server: Name or service not known Init SSL without certificate database battery.charge: 100 battery.charge.low: 10 battery.charge.warning: 20 battery.mfr.date: CPS battery.runtime: 3825 battery.runtime.low: 300 battery.type: PbAcid battery.voltage: 27.5 battery.voltage.nominal: 24 device.mfr: CPS device.model: CP1500PFCLCDa device.serial: CXXKU2004605 device.type: ups driver.name: usbhid-ups driver.parameter.pollfreq: 30 driver.parameter.pollinterval: 2 driver.parameter.port: auto driver.parameter.productid: 0601 driver.parameter.serial: CXXKU2004605 driver.parameter.synchronous: no driver.parameter.vendorid: 0764 driver.version: 2.7.4 driver.version.data: CyberPower HID 0.4 driver.version.internal: 0.41 input.voltage: 120.0 input.voltage.nominal: 120 output.voltage: 136.0 ups.beeper.status: enabled ups.delay.shutdown: 20 ups.delay.start: 30 ups.load: 10 ups.mfr: CPS ups.model: CP1500PFCLCDa ups.productid: 0601 ups.realpower.nominal: 1000 ups.serial: CXXKU2004605 ups.status: OL ups.test.result: No test initiated ups.timer.shutdown: -60 ups.timer.start: -60 ups.vendorid: 0764 [email protected]:/etc/nut
As the clients, there are only two files we need to configure. The files are
upsmon.conf and they are located in
/etc/nut/. First, we need to install nut-client to the client nodes. Technically, the only thing is needed is nut-client; however, I could not get the nut-client.service to start. Installing the
nut package worked.
apt install nut
Once the nut-client has been installed, we need change the mode from none to netclient.
sed -i 's/MODE=none/MODE=netclient/' /etc/nut/nut.conf
We need to configure the uspmon.conf similar to what what we did to the RPi NUT server. However, we are going to be using the remote user.
echo "MONITOR [email protected] 1 upsmon_remote s3cR3tpa$5w0rd slave" >> /etc/nut/upsmon.conf
Once the files has been updated, we need to enable and start the nut-monitor and nut-server services.
systemctl enable --now nut-server systemctl enable --now nut-monitor
You can run the command upsc [email protected] and get the UPS’ info.
Now, back to the RPi NUT server, you should see a log stating that the remote nut has logged in as shown below.
# Run tail -f /var/log/syslog on the nut server Jan 29 11:47:50 nut-server upsd: User [email protected] logged into UPS [ups1]