# logfile - write a logfile

Writes a log file of the status of monitors.

The logfile format is:

    datetime monitor-name: status; VFC=vfc (message) (execution-time)

where the fields have the following meanings:

datetime

  the datetime of the entry. Format is controlled by the `dateformat` configuration option.

monitor-name

  the name of the monitor

status

  either `ok` if the monitor succeeded, or `failed since YYYY-MM-DD HH:MM:SS`

vfc

  the virtual failure count: the number of failures of the monitor beyond its tolerance. Not present for ok lines.

message

  the message the monitor recorded as the reason for failure. Not present for ok lines.

execution-time

  the time the monitor took to execute its check

filename
  Type:

    string

  Required:

    true

  the filename to write to. Rotating this file underneath SimpleMonitor will likely result to breakage. If you would like the logfile to rotate automatically based on size or age, see the logfileng logger.

buffered
  Type:

    boolean

  Required:

    false

  Default:

    true

  disable to use unbuffered writes to the logfile, allowing it to be watched in real time. Otherwise, you will find that updates don’t appear in the file immediately.

only_failures
  Type:

    boolean

  Required:

    false

  Default:

    false

  set to have only monitor failures written to the log file (almost, but not quite, turning it into an alerter)