This plugin provides native disk instrumentation for monitoring and metrics collection, including: health, usage, and various metrics.
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Check disk capacity and inodes based upon the gem sys-filesystem.

Can adjust thresholds for larger filesystems by providing a 'magic factor' (-m). The default, 1.0, will not adapt threshold percentages for volumes.

The -l option can be used in combination with the 'magic factor' to specify the minimum size volume to adjust the thresholds for.

Refer to check_mk's documentation on adaptive thresholds.

You can also visualize the adjustment using WolframAlpha with the following:

y = 100 - (100-P)*(N^(1-m))/(x^(1-m)), y = P for x in 0 to 1024

Where P = base percentage, N = normalize factor, and m = magic factor


Check the mount points in /etc/fstab to ensure they are all accounted for.


Acquire disk capacity metrics from df and convert them to a form usable by graphite


Read /proc/iostats for disk metrics and put them in a form usable by Graphite. See iostats.txt for more details.


Based on disk-capacity-metrics.rb by bhenerey and nstielau. The difference here being how the key is defined in graphite and the size we emit to graphite(now using megabytes), inode info has also been dropped.


Check the SMART status of hardrives and alert based upon a given set of thresholds


Check the health of a disk using smartctl


Check the status of SMART offline tests and optionally check if tests were executed in a specified interval


  • bin/check-disk-usage.rb
  • bin/check-fstab-mounts.rb
  • bin/check-smart-status.rb
  • bin/check-smart.rb
  • bin/check-smart-tests.rb
  • bin/metrics-disk.rb
  • bin/metrics-disk-capacity.rb
  • bin/metrics-disk-usage.rb


This is a sample input file used by check-smart-status and check-smart, see the script for further details.

  "smart": {
    "attributes": [
      { "id": 1, "name": "Raw_read_Error_Rate", "read": "left16bit" },
      { "id": 5, "name": "Reallocated_Sector_Ct" },
      { "id": 9, "name": "Power_On_Hours", "read": "right16bit", "warn_max": 10000, "crit_max": 15000 },
      { "id": 10 , "name": "Spin_Retry_Count" },
      { "id": 184, "name": "End-to-End_Error" },
      { "id": 187, "name": "Reported_Uncorrect" },
      { "id": 188, "name": "Command_Timeout" },
      { "id": 193, "name": "Load_Cycle_Count", "warn_max": 300000, "crit_max": 600000 },
      { "id": 194, "name": "Temperature_Celsius", "read": "right16bit", "crit_min": 20, "warn_min": 10, "warn_max": 40, "crit_max": 50 },
      { "id": 196, "name": "Reallocated_Event_Count" },
      { "id": 197, "name": "Current_Pending_Sector" },
      { "id": 198, "name": "Offline_Uncorrectable" },
      { "id": 199, "name": "UDMA_CRC_Error_Count" },
      { "id": 201, "name": "Unc_Soft_read_Err_Rate", "read": "left16bit" },
      { "id": 230, "name": "Life_Curve_Status", "crit_min": 100, "warn_min": 100, "warn_max": 100, "crit_max": 100 }
  "hardware": {
    "devices": [
	  { "path": "sda", "ignore" : [ 187 ] },
	  { "path": "sdb", "override": "/dev/twa0 -d 3ware,0" }


Installation and Setup


Certification Verification

If you are verifying certificates in the gem install you will need the certificate for the sys-filesystem gem loaded in the gem certificate store. That cert can be found here.