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Logging
editLogging
editThe logging
section of the filebeat.yml
config file contains options
for configuring the Beats logging output. The logging system can write logs to
the syslog or rotate log files. If logging is not explicitly configured, file
output is used on Windows systems, and syslog output is used on Linux and OS X.
logging.level: warning logging.to_files: true logging.to_syslog: false logging.files: path: /var/log/mybeat name: mybeat.log keepfiles: 7
In addition to setting logging options in the config file, you can modify the logging output configuration from the command line. See Command Line Options.
Logging Options
editYou can specify the following options in the logging
section of the filebeat.yml
config file:
to_syslog
editWhen true, writes all logging output to the syslog.
to_files
editWhen true, writes all logging output to files. The log files are automatically rotated when the log file size limit is reached.
Filebeat only creates a log file if there is logging output. For
example, if you set the log level
to error
and there are no errors,
there will be no log file in the directory specified for logs.
level
editMinimum log level. One of debug
, info
, warning
, error
, or critical
.
The default log level is info
.
-
debug
-
Logs debug messages, including a detailed printout of all events
flushed by the Beat. Also logs informational messages, warnings, errors, and
critical errors. When the log level is
debug
, you can specify a list ofselectors
to display debug messages for specific components. If no selectors are specified, the*
selector is used to display debug messages for all components. -
info
- Logs informational messages, including the number of events that are published. Also logs any warnings, errors, or critical errors.
-
warning
- Logs warnings, errors, and critical errors.
-
error
- Logs errors and critical errors.
-
critical
- Logs critical errors only.
selectors
editThe list of debugging-only selector tags used by different Beats components. Use *
to enable debug output for all components. For example add publish
to display
all the debug messages related to event publishing. When starting the Beat,
selectors can be overwritten using the -d
command line option (-d
also sets
the debug log level).
metrics.enabled
editIf enabled, Filebeat periodically logs its internal metrics that have changed in the last period. For each metric that changed, the delta from the value at the beginning of the period is logged. Also, the total values for all non-zero internal metrics are logged on shutdown. The default is true.
Here is an example log line:
2016/07/04 12:16:10.821047 logp.go:194: INFO Non-zero metrics in the last 30s: libbeatEsPublishedAndAckedEvents=18 libbeatEsPublishWriteBytes=10045
Note that we currently offer no backwards compatible guarantees for the internal metrics and for this reason they are also not documented.
metrics.period
editThe period after which to log the internal metrics. The default is 30s.
files.path
editThe directory that log files are written to. The default is the logs path. See the Directory Layout section for details.
files.name
editThe name of the file that logs are written to. By default, the name of the Beat is used.
files.rotateeverybytes
editThe maximum size of a log file. If the limit is reached, a new log file is generated. The default size limit is 10485760 (10 MB).
files.keepfiles
editThe number of most recent rotated log files to keep on disk. Older files are
deleted during log rotation. The default value is 7. The keepfiles
options has to be
in the range of 2 to 1024 files.
Logging Format
editThe logging format is different for each logging type:
- to syslog: Syslog adds the timestamp itself.
-
to file: RFC 3339 format is used for the timestamp:
2006-01-02T15:04:05Z07:00 WARN log-message
. The format includes the timezone followed by the logging level. -
to stderr: UTC format is used for the timestamp:
2015/11/12 09:03:37.369262 geolite.go:52: WARN log-message
. The format includes the UTC timestamp with the milliseconds, then the name of the caller that sent the log entry followed by the logging level. This option should be used mainly for debugging.