Journald inputedit

This functionality is in technical preview and may be changed or removed in a future release. Elastic will apply best effort to fix any issues, but features in technical preview are not subject to the support SLA of official GA features.

journald is a system service that collects and stores logging data. The journald input reads this log data and the metadata associated with it.

The simplest configuration example is one that reads all logs from the default journal.

filebeat.inputs:
- type: journald
  id: everything

You may wish to have separate inputs for each service. You can use include_matches to specify a list of filter expressions that are applied as a logical OR. A good way to list the journald fields that are available for filtering messages is to run journalctl -o json to output logs and metadata as JSON. This example collects logs from the vault.service systemd unit.

filebeat.inputs:
- type: journald
  id: service-vault
  include_matches:
    - _SYSTEMD_UNIT=vault.service

This example collects kernel logs where the message begins with iptables. Note that include_matches is more efficient than Beat processors because that are applied before the data is passed to the Filebeat so prefer them where possible.

filebeat.inputs:
- type: journald
  id: iptables
  include_matches:
    - _TRANSPORT=kernel
  processors:
    - drop_event:
        when.not.regexp.message: '^iptables'

Each example adds the id for the input to ensure the cursor is persisted to the registry with a unique ID. The ID should be unique among journald inputs. If you don’t specify and id then one is created for you by hashing the configuration. So when you modify the config this will result in a new ID and a fresh cursor.

Configuration optionsedit

The journald input supports the following configuration options plus the Common options described later.

idedit

An optional unique identifier for the input. By providing a unique id you can operate multiple inputs on the same journal. This allows each input’s cursor to be persisted independently in the registry file.

filebeat.inputs:
- type: journald
  id: consul.service
  include_matches:
    - _SYSTEMD_UNIT=consul.service

- type: journald
  id: vault.service
  include_matches:
    - _SYSTEMD_UNIT=vault.service

pathsedit

A list of paths that will be crawled and fetched. Each path can be a directory path (to collect events from all journals in a directory), or a file path. If you specify a directory, Filebeat merges all journals under the directory into a single journal and reads them.

If no paths are specified, Filebeat reads from the default journal.

backoffedit

The number of seconds to wait before trying to read again from journals. The default is 1s.

max_backoffedit

The maximum number of seconds to wait before attempting to read again from journals. The default is 60s.

seekedit

The position to start reading the journal from. Valid settings are:

  • head: Starts reading at the beginning of the journal. After a restart, Filebeat resends all log messages in the journal.
  • tail: Starts reading at the end of the journal. After a restart, Filebeat resends the last message, which might result in duplicates. If multiple log messages are written to a journal while Filebeat is down, only the last log message is sent on restart.
  • cursor: On first read, starts reading at the beginning of the journal. After a reload or restart, continues reading at the last known position.

If you have old log files and want to skip lines, start Filebeat with seek: tail specified. Then stop Filebeat, set seek: cursor, and restart Filebeat.

include_matchesedit

A list of filter expressions used to match fields. The format of the expression is field=value. Filebeat fetches all events that exactly match the expressions. Pattern matching is not supported.

To reference fields, use one of the following:

  • The field name used by the systemd journal. For example, CONTAINER_TAG=redis.
  • The translated field name used by Filebeat. For example, container.image.tag=redis. Filebeat does not translate all fields from the journal. For custom fields, use the name specified in the systemd journal.

Translated field namesedit

You can use the following translated names in filter expressions to reference journald fields:

Journald field name

Translated name

COREDUMP_UNIT

journald.coredump.unit

COREDUMP_USER_UNIT

journald.coredump.user_unit

OBJECT_AUDIT_LOGINUID

journald.object.audit.login_uid

OBJECT_AUDIT_SESSION

journald.object.audit.session

OBJECT_CMDLINE

journald.object.cmd

OBJECT_COMM

journald.object.name

OBJECT_EXE

journald.object.executable

OBJECT_GID

journald.object.gid

OBJECT_PID

journald.object.pid

OBJECT_SYSTEMD_OWNER_UID

journald.object.systemd.owner_uid

OBJECT_SYSTEMD_SESSION

journald.object.systemd.session

OBJECT_SYSTEMD_UNIT

journald.object.systemd.unit

OBJECT_SYSTEMD_USER_UNIT

journald.object.systemd.user_unit

OBJECT_UID

journald.object.uid

_AUDIT_LOGINUID

process.audit.login_uid

_AUDIT_SESSION

process.audit.session

_BOOT_ID

host.boot_id

_CAP_EFFECTIVE

process.capabilites

_CMDLINE

process.cmd

_CODE_FILE

journald.code.file

_CODE_FUNC

journald.code.func

_CODE_LINE

journald.code.line

_COMM

process.name

_EXE

process.executable

_GID

process.uid

_HOSTNAME

host.name

_KERNEL_DEVICE

journald.kernel.device

_KERNEL_SUBSYSTEM

journald.kernel.subsystem

_MACHINE_ID

host.id

_MESSAGE

message

_PID

process.pid

_PRIORITY

syslog.priority

_SYSLOG_FACILITY

syslog.facility

_SYSLOG_IDENTIFIER

syslog.identifier

_SYSLOG_PID

syslog.pid

_SYSTEMD_CGROUP

systemd.cgroup

_SYSTEMD_INVOCATION_ID

systemd.invocation_id

_SYSTEMD_OWNER_UID

systemd.owner_uid

_SYSTEMD_SESSION

systemd.session

_SYSTEMD_SLICE

systemd.slice

_SYSTEMD_UNIT

systemd.unit

_SYSTEMD_USER_SLICE

systemd.user_slice

_SYSTEMD_USER_UNIT

systemd.user_unit

_TRANSPORT

systemd.transport

_UDEV_DEVLINK

journald.kernel.device_symlinks

_UDEV_DEVNODE

journald.kernel.device_node_path

_UDEV_SYSNAME

journald.kernel.device_name

_UID

process.uid

The following translated fields for Docker are also available:

CONTAINER_ID

container.id_truncated

CONTAINER_ID_FULL

container.id

CONTAINER_NAME

container.name

CONTAINER_PARTIAL_MESSAGE

container.partial

CONTAINER_TAG

container.image.tag

Common optionsedit

The following configuration options are supported by all inputs.

enablededit

Use the enabled option to enable and disable inputs. By default, enabled is set to true.

tagsedit

A list of tags that Filebeat includes in the tags field of each published event. Tags make it easy to select specific events in Kibana or apply conditional filtering in Logstash. These tags will be appended to the list of tags specified in the general configuration.

Example:

filebeat.inputs:
- type: journald
  . . .
  tags: ["json"]
fieldsedit

Optional fields that you can specify to add additional information to the output. For example, you might add fields that you can use for filtering log data. Fields can be scalar values, arrays, dictionaries, or any nested combination of these. By default, the fields that you specify here will be grouped under a fields sub-dictionary in the output document. To store the custom fields as top-level fields, set the fields_under_root option to true. If a duplicate field is declared in the general configuration, then its value will be overwritten by the value declared here.

filebeat.inputs:
- type: journald
  . . .
  fields:
    app_id: query_engine_12
fields_under_rootedit

If this option is set to true, the custom fields are stored as top-level fields in the output document instead of being grouped under a fields sub-dictionary. If the custom field names conflict with other field names added by Filebeat, then the custom fields overwrite the other fields.

processorsedit

A list of processors to apply to the input data.

See Processors for information about specifying processors in your config.

pipelineedit

The ingest pipeline ID to set for the events generated by this input.

The pipeline ID can also be configured in the Elasticsearch output, but this option usually results in simpler configuration files. If the pipeline is configured both in the input and output, the option from the input is used.

keep_nulledit

If this option is set to true, fields with null values will be published in the output document. By default, keep_null is set to false.

indexedit

If present, this formatted string overrides the index for events from this input (for elasticsearch outputs), or sets the raw_index field of the event’s metadata (for other outputs). This string can only refer to the agent name and version and the event timestamp; for access to dynamic fields, use output.elasticsearch.index or a processor.

Example value: "%{[agent.name]}-myindex-%{+yyyy.MM.dd}" might expand to "filebeat-myindex-2019.11.01".

publisher_pipeline.disable_hostedit

By default, all events contain host.name. This option can be set to true to disable the addition of this field to all events. The default value is false.