Disk Input Plugin

This plugin gathers metrics about disk usage.

[!NOTE] The used_percent field is calculated by used / (used + free) and not used / total as the unix df command does it. See wikipedia - df for more details.

⭐ Telegraf v0.1.1 🏷️ system 💻 all

Global configuration options

Plugins support additional global and plugin configuration settings for tasks such as modifying metrics, tags, and fields, creating aliases, and configuring plugin ordering. See CONFIGURATION.md for more details.

Configuration

toml

# Read metrics about disk usage by mount point
[[inputs.disk]]
  ## By default stats will be gathered for all mount points.
  ## Set mount_points will restrict the stats to only the specified mount points.
  # mount_points = ["/"]

  ## Ignore mount points by filesystem type.
  ignore_fs = ["tmpfs", "devtmpfs", "devfs", "iso9660", "overlay", "aufs", "squashfs"]

  ## Ignore mount points by mount options.
  ## The 'mount' command reports options of all mounts in parathesis.
  ## Bind mounts can be ignored with the special 'bind' option.
  # ignore_mount_opts = []

Docker container

To monitor the Docker engine host from within a container you will need to mount the host's filesystem into the container and set the HOST_PROC environment variable to the location of the /proc filesystem. If desired, you can also set the HOST_MOUNT_PREFIX environment variable to the prefix containing the /proc directory, when present this variable is stripped from the reported path tag.

shell

docker run -v /:/hostfs:ro -e HOST_MOUNT_PREFIX=/hostfs -e HOST_PROC=/hostfs/proc telegraf

Metrics

disk
- tags:
  - fstype (filesystem type)
  - device (device file)
  - path (mount point path)
  - mode (whether the mount is rw or ro)
  - label (devicemapper labels, only if present)
- fields:
  - 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)
  - inodes_used_percent (float, percent)

Troubleshooting

On Linux, the list of disks is taken from the /proc/self/mounts file and a statfs call is made on the second column. If any expected filesystems are missing ensure that the telegraf user can read these files:

shell

$ sudo -u telegraf cat /proc/self/mounts | grep sda2
/dev/sda2 /home ext4 rw,relatime,data=ordered 0 0
$ sudo -u telegraf stat /home

It may be desired to use POSIX ACLs to provide additional access:

shell

sudo setfacl -R -m u:telegraf:X /var/lib/docker/volumes/

Example Output

text

disk,fstype=hfs,mode=ro,path=/ free=398407520256i,inodes_free=97267461i,inodes_total=121847806i,inodes_used=24580345i,total=499088621568i,used=100418957312i,used_percent=20.131039916242397,inodes_used_percent=20.1729894 1453832006274071563
disk,fstype=devfs,mode=rw,path=/dev free=0i,inodes_free=0i,inodes_total=628i,inodes_used=628i,total=185856i,used=185856i,used_percent=100,inodes_used_percent=100 1453832006274137913
disk,fstype=autofs,mode=rw,path=/net free=0i,inodes_free=0i,inodes_total=0i,inodes_used=0i,total=0i,used=0i,used_percent=0,inodes_used_percent=0 1453832006274157077
disk,fstype=autofs,mode=rw,path=/home free=0i,inodes_free=0i,inodes_total=0i,inodes_used=0i,total=0i,used=0i,used_percent=0,inodes_used_percent=0 1453832006274169688
disk,device=dm-1,fstype=xfs,label=lvg-lv,mode=rw,path=/mnt inodes_free=8388605i,inodes_used=3i,total=17112760320i,free=16959598592i,used=153161728i,used_percent=0.8950147441789215,inodes_total=8388608i,inodes_used_percent=0.0017530778 1677001387000000000