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
wikipedia - df for more details.
Global configuration options
In addition to the plugin-specific configuration settings, plugins support
additional global and plugin configuration settings. These settings are used to
modify metrics, tags, and field or create aliases and configure ordering, etc.
See the CONFIGURATION.md for more details.
Configuration
# 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.
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:
$ 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:
sudo setfacl -R -m u:telegraf:X /var/lib/docker/volumes/
Example Output
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