telegraf/plugins/inputs/system/DISK_README.md

2.3 KiB

Disk Input Plugin

The disk input plugin gathers metrics about disk usage.

Note that used_percent is calculated by doing used / (used + free), not used / total, which is how the unix df command does it. See https://en.wikipedia.org/wiki/Df_(Unix) for more details.

Configuration:

# Read metrics about disk usage by mount point
[[inputs.disk]]
  # By default, telegraf gather stats for all mountpoints.
  # Setting mountpoints will restrict the stats to the specified mountpoints.
  # mount_points = ["/"]

Additionally, the behavior of resolving the mount_points can be configured by using the HOST_MOUNT_PREFIX environment variable. When present, this variable is prepended to the mountpoints discovered by the plugin before retrieving stats. The prefix is stripped from the reported path in the measurement. This settings is useful when running telegraf inside a docker container to report host machine metrics. In this case, the host's root volume should be mounted into the container and the HOST_MOUNT_PREFIX and HOST_ETC environment variables set.

docker run -v /:/hostfs:ro -e HOST_MOUNT_PREFIX=/hostfs -e HOST_ETC=/hostfs/etc telegraf-docker

Measurements & Fields:

  • disk
    • free (integer, bytes)
    • total (integer, bytes)
    • used (integer, bytes)
    • used_percent (float, percent)
    • inodes_free (integer, files)
    • inodes_total (integer, files)
    • inodes_used (integer, files)

Tags:

  • All measurements have the following tags:
    • fstype (filesystem type)
    • path (mount point path)

Example Output:

% ./telegraf -config ~/ws/telegraf.conf -input-filter disk -test
* Plugin: disk, Collection 1
> disk,fstype=hfs,path=/ free=398407520256i,inodes_free=97267461i,inodes_total=121847806i,inodes_used=24580345i,total=499088621568i,used=100418957312i,used_percent=20.131039916242397 1453832006274071563
> disk,fstype=devfs,path=/dev free=0i,inodes_free=0i,inodes_total=628i,inodes_used=628i,total=185856i,used=185856i,used_percent=100 1453832006274137913
> disk,fstype=autofs,path=/net free=0i,inodes_free=0i,inodes_total=0i,inodes_used=0i,total=0i,used=0i,used_percent=0 1453832006274157077
> disk,fstype=autofs,path=/home free=0i,inodes_free=0i,inodes_total=0i,inodes_used=0i,total=0i,used=0i,used_percent=0 1453832006274169688