Check manual page of diskstat

diskstat

Author: Mathias Kettner

License: GPL

Distribution: official part of Check_MK

Supported Agents: Linux

This check measures the throughput of block devices (disks) on Linux hosts. You can either have a single check for every single disk (which is the default) or a summary check summing up the throughput of all disks.

For legacy reasons it is also possible (but not advisable) to have all disks summarized but with a separate check for read and write (this is how this check worked up to version 1.1.10).

You can apply separate warning and critical levels for the read and write throughput. Optionally you can have the check compute average values on a configurable time period and have the levels applied on the average instead of the current values. This makes it possible to ignore short "peaks" and only trigger and longer phases of high disk activity.

Item

Either "SUMMARY" for a summarized check of alls disks or the name of the disk device, e.g. "sda". In order to support configurations up to version 1.1.10 also the items "read" and "write" are supported.

Check parameters

Parameter	Type	Description
"read":		The levels to be applied to the read throughput. It this entry is None or missing in the dictionary, then no levels are applied. This is the defaut. The values are in MB per second. Setting "read" to (20, 40) will warn if 20 MB/s is exceeded and make the check critical at 40 MB/s. If averaging is turned on, then the levels are applied to the averaged values!
"write":		The levels for the write throughput.
"average":		If this is not None, it will be interpreted as a time range in minutes to do averaging over. Set this to 15 in order to have the levels applied to a 15-minute average instead of the current values (approx.). Turning the average on will also create two additional performance values. Make sure that your graphing tool is setup to a changing number of variables.

Performance data

The disk throughput for read and write in bytes per second. If averaging is turned on, then two additional values are sent: the averaged read and write throughput.

In the legacy mode only one variable: the throughput since the last check in in bytes(!) per second, either for read or for write.

Inventory

The inventory is configured via diskstat_inventory_mode. If this is set to "single" (the default), then one check will be created for each disk. If it is set to "summary" then only one service per host will be created that has at least one hard disk. If set to "legacy" then a separate check for read and write will be created (deprecated).

Configuration variables

Variable	Type	Description
diskstat_defaul_levels	dict	The default parameter used for inventorized checks. This is preset to the empty dictionary. That means that no averaging is done and no levels are applied.
diskstat_inventory_mode	string	Either "single" for one service per disk or "summary" for the throughput of all disks summed up in one service. Also possible is "legacy" for the old style mode (see above). Default is "single".

Examples

# switch inventory behaviour to 1.1.10 mode
diskstat_inventory_mode = "legacy"

# alternative: create one check for all disks
diskstat_inventory_mode = "summary"

# Set default levels for diskstat
diskstat_default_levels = {
  "read" :    (10, 20),   # level for read MB/sec
  "write" :   (20, 40),   # level for write MB/sec
  "average" : 15,         # averaging in minutes
}

# Alternative: just enable averaging over 10 minutes,
# do not apply levels:
diskstat_default_levels = {
    "average" : 15
}

# Settings for certain hosts:
check_parameters += [
  ( {"write" : (20, 50), "average" : 10 }, [ "oracle" ], ALL_HOSTS, [ "Disk IO" ])
]