unraid-simple-monitoring-api

Table of Contents

1. What is this
2. Utilization with Unraid
   1. Installation
   2. Configuration
3. Integration with Homepage
   1. Configuration
4. How reliable are the measurements?

What is this?

Simple rest API to monitor basic metrics, currently supports:

• Disk utilization
• Network traffic
• CPU load

Originally created for use with Homepage.

Utilization with Unraid

Installation

Install from the Unraid community apps

Configuration

By default the application expects a configuration file in

/mnt/user/appdata/unraid-simple-monitoring-api/conf.yml

You can find an example file here. It should look like this

networks:
  - eth0
  - anotherNetwork
disks:
  cache:
    - /mnt/cache
    - /another/cache/mount
  array:
    - /mnt/disk1
    - /mnt/disk2

Utilization

Make a request to

http://your-unraid-ip:24940

The response will be formatted this way.

{
   "array":[
      {
         "mount":"/mnt/disk1",
         "total":906,
         "used":515,
         "free":391,
         "free_percent":43.16,
         "used_percent":56.84
      }
   ],
   "cache":[
      {
         "mount":"/",
         "total":906,
         "used":515,
         "free":391,
         "free_percent":43.16,
         "used_percent":56.84
      }
   ],
   "network":[
      {
         "interface":"enp42s0",
         "rx_MiBs":0.81,
         "tx_MiBs":0.03,
         "rx_Mbps":6.84,
         "tx_Mbps":0.22
      },
      {
         "interface":"eth0",
         "rx_MiBs":0,
         "tx_MiBs":0,
         "rx_Mbps":0,
         "tx_Mbps":0
      }
   ],
   "array_total":{
      "mount":"total",
      "total":906,
      "used":515,
      "free":391,
      "free_percent":43.16,
      "used_percent":56.84
   },
   "cache_total":{
      "mount":"total",
      "total":906,
      "used":515,
      "free":391,
      "free_percent":43.16,
      "used_percent":56.84
   },
   "network_total":{
      "interface":"total",
      "rx_MiBs":0.81,
      "tx_MiBs":0.03,
      "rx_Mbps":6.84,
      "tx_Mbps":0.22
   },
   "cpu": {
      "load_percent":3.79
   }
}

Integration with Homepage

Configuration

Official homepage custom API widget documentation: https://gethomepage.dev/latest/widgets/services/customapi/.
Your homepage services.yml should look like this if you want for example cache and network data. Homepage limits the widget to 4 items.

- Category:
   - Unraid:
        icon: unraid.png
        href: http://<your-unraid-ip>
        widget:
          type: customapi
          url: http://<your-unraid-ip>:24940
          method: GET # this doesn't matter
          mappings:
            - field:
                cache_total: free
              label: cache free
              format: number
              suffix: "GiB"
            - field:
                cache_total: free_percent
              label: percent
              format: percent
            - field:
                network_total: rx_MiBs
              label: rx
              format: float
              suffix: MiB/s
            - field:
                network_total: tx_MiBs
              label: tx
              format: float
              suffix: MiB/s

How reliable are the measurements?

The goal of this API is to be simple, fast, and lightweight.
For these reasons, the measurements provided are not as accurate as they could be.

Disk

Disk utilization is rounded down to the nearest GiB.

Network and CPU

Both Network and CPU usage need to be measured for some time interval. Typically, to get an accurate measurement, you would monitor these for a few seconds before providing a response.
To avoid having to either:

• wait for the measurement to be completed before responding
• continuosly measure them to have a recent measurement ready to respond with

A different approach has been taken: a snapshot of Network and CPU usage is taken every time the API is called, and the response is the average Network and CPU usage between the current and last API call. This ensures that the response is quick and reasonably accurate, without having the process continuously read Network and CPU data even when not required.