PowerMon

PowerMon tracks the power usage on your host and can report on both consumption and cost, using a python script installed on the host.

PowerMon consumption graph

Currently the script uses one of two methods to determine current power usage:

ACPI via libsensors
HP-Health (HP Proliant servers only)

The ACPI method is quite unreliable as it is usually only implemented by battery-powered devices, e.g. laptops. YMMV. However, it's possible to support any method as long as it can return a power value, usually in Watts.

Tip

You can achieve this by adding a method and a function for that method to the script. It should be called by getData() and return a dictionary.

Because the methods are unreliable for all hardware, you need to declare to the script which method to use. The are several options to assist with testing, see the --help.

SNMP Extend

Initial setup

Download the python script onto the host:

wget https://raw.githubusercontent.com/librenms/librenms-agent/master/snmp/powermon-snmp.py -O /usr/local/bin/powermon-snmp.py

Make the script executable:

chmod +x /usr/local/bin/powermon-snmp.py

Edit the script and set the cost per kWh for your supply. You must uncomment this line for the script to work:
```
vi /usr/local/bin/powermon-snmp.py
#costPerkWh = 0.15
```

Choose you method below:

Method 1. sensorsMethod 2. hpasmcli

Install dependencies:

dnf install lm_sensors
pip install PySensors

Test the script from the command-line. For example:

$ /usr/local/bin/powermon-snmp.py -m sensors -n -p
{
  "meter": {
    "0": {
      "reading": 0.0
    }
  },
  "psu": {},
  "supply": {
    "rate": 0.15
  },
  "reading": "0.0"
}

If you see a reading of 0.0 it is likely this method is not supported for your system. If not, continue.

Obtain the hp-health package for your system. Generally there are three options:
- Standalone package from HPE Support
- From the HP Management Component Pack (MCP).
- Included in the HP Service Pack for Proliant (SPP)
If you've downloaded the standalone package, install it. For example:
```
rpm -ivh hp-health-10.91-1878.11.rhel8.x86_64.rpm
```
Check the service is running:
```
systemctl status hp-health
```

Test the script from the command-line. For example:

$ /usr/local/bin/powermon-snmp.py -m hpasmcli -n -p
{
  "meter": {
    "1": {
      "reading": 338.0
    }
  },
  "psu": {
    "1": {
      "present": "Yes",
      "redundant": "No",
      "condition": "Ok",
      "hotplug": "Supported",
      "reading": 315.0
    },
    "2": {
      "present": "Yes",
      "redundant": "No",
      "condition": "FAILED",
      "hotplug": "Supported"
    }
  },
  "supply": {
    "rate": 0.224931
  },
  "reading": 338.0
}

If you see a reading of 0.0 it is likely this method is not supported for your system. If not, continue.

Finishing Up

Edit your snmpd.conf file (usually /etc/snmp/snmpd.conf) and add the following:
```
extend  powermon   /usr/local/bin/powermon-snmp.py -m hpasmcli
```
NOTE: Avoid using other script options in the snmpd config as the results may not be interpreted correctly by LibreNMS.
Reload your snmpd service:
```
systemctl reload snmpd
```
You're now ready to enable the application in LibreNMS.