Configure the Logstash output
editConfigure the Logstash output
editThe Logstash output sends events directly to Logstash by using the lumberjack protocol, which runs over TCP. Logstash allows for additional processing and routing of generated events.
Prerequisite
To send events to Logstash, you also need to create a Logstash configuration pipeline that listens for incoming Beats connections and indexes the received events into Elasticsearch. For more information, see Getting Started with Logstash. Also see the documentation for the Beats input and Elasticsearch output plugins.
If you want to use Logstash to perform additional processing on the data collected by Filebeat, you need to configure Filebeat to use Logstash.
To do this, edit the Filebeat configuration file to disable the Elasticsearch output by commenting it out and enable the Logstash output by uncommenting the Logstash section:
output.logstash: hosts: ["127.0.0.1:5044"]
The hosts
option specifies the Logstash server and the port (5044
) where Logstash is configured to listen for incoming
Beats connections.
For this configuration, you must load the index template into Elasticsearch manually because the options for auto loading the template are only available for the Elasticsearch output.
Want to use Filebeat modules with Logstash? You need to do some extra setup. For more information, see Working with Filebeat modules.
Accessing metadata fields
editEvery event sent to Logstash contains the following metadata fields that you can use in Logstash for indexing and filtering:
Filebeat uses the |
|
The default is filebeat. To change this value, set the
|
|
The current version of Filebeat. |
You can access this metadata from within the Logstash config file to set values dynamically based on the contents of the metadata.
For example, the following Logstash configuration file tells Logstash to use the index reported by Filebeat for indexing events into Elasticsearch:
input { beats { port => 5044 } } output { elasticsearch { hosts => ["http://localhost:9200"] index => "%{[@metadata][beat]}-%{[@metadata][version]}" action => "create" } }
|
Events indexed into Elasticsearch with the Logstash configuration shown here will be similar to events directly indexed by Filebeat into Elasticsearch.
If ILM is not being used, set index
to %{[@metadata][beat]}-%{[@metadata][version]}-%{+YYYY.MM.dd}
instead so Logstash creates an index per day, based on the @timestamp
value of the events coming from Beats.
Compatibility
editThis output works with all compatible versions of Logstash. See the Elastic Support Matrix.
Configuration options
editYou can specify the following options in the logstash
section of the
filebeat.yml
config file:
enabled
editThe enabled config is a boolean setting to enable or disable the output. If set to false, the output is disabled.
The default value is true
.
hosts
editThe list of known Logstash servers to connect to. If load balancing is disabled, but multiple hosts are configured, one host is selected randomly (there is no precedence). If one host becomes unreachable, another one is selected randomly.
All entries in this list can contain a port number. The default port number 5044 will be used if no number is given.
compression_level
editThe gzip compression level. Setting this value to 0 disables compression. The compression level must be in the range of 1 (best speed) to 9 (best compression).
Increasing the compression level will reduce the network usage but will increase the CPU usage.
The default value is 3.
escape_html
editConfigure escaping of HTML in strings. Set to true
to enable escaping.
The default value is false
.
worker
or workers
editThe number of workers per configured host publishing events to Logstash. This is best used with load balancing mode enabled. Example: If you have 2 hosts and 3 workers, in total 6 workers are started (3 for each host).
loadbalance
editWhen loadbalance: true
is set, Filebeat connects to all configured
hosts and sends data through all connections in parallel. If a connection
fails, data is sent to the remaining hosts until it can be reestablished.
Data will still be sent as long as Filebeat can connect to at least
one of its configured hosts.
When loadbalance: false
is set, Filebeat sends data to a single host
at a time. The target host is chosen at random from the list of configured
hosts, and all data is sent to that target until the connection fails, when
a new target is selected. Data will still be sent as long as Filebeat
can connect to at least one of its configured hosts. To rotate through the
list of configured hosts over time, use this option in conjunction with the
ttl
setting to close the connection at the configured interval and choose
a new target host.
The default value is false
.
output.logstash: hosts: ["localhost:5044", "localhost:5045"] loadbalance: true index: filebeat
ttl
editTime to live for a connection to Logstash after which the connection will be re-established. Useful when Logstash hosts represent load balancers. Since the connections to Logstash hosts are sticky, operating behind load balancers can lead to uneven load distribution between the instances. Specifying a TTL on the connection allows to achieve equal connection distribution between the instances. Specifying a TTL of 0 will disable this feature.
The default value is 0. This setting accepts duration data type values.
The "ttl" option is not yet supported on an async Logstash client (one with the "pipelining" option set).
pipelining
editConfigures the number of batches to be sent asynchronously to Logstash while waiting
for ACK from Logstash. Output only becomes blocking once number of pipelining
batches have been written. Pipelining is disabled if a value of 0 is
configured. The default value is 2.
proxy_url
editThe URL of the SOCKS5 proxy to use when connecting to the Logstash servers. The
value must be a URL with a scheme of socks5://
. The protocol used to
communicate to Logstash is not based on HTTP so a web-proxy cannot be used.
If the SOCKS5 proxy server requires client authentication, then a username and password can be embedded in the URL as shown in the example.
When using a proxy, hostnames are resolved on the proxy server instead of on the
client. You can change this behavior by setting the
proxy_use_local_resolver
option.
output.logstash: hosts: ["remote-host:5044"] proxy_url: socks5://user:password@socks5-proxy:2233
proxy_use_local_resolver
editThe proxy_use_local_resolver
option determines if Logstash hostnames are
resolved locally when using a proxy. The default value is false, which means
that when a proxy is used the name resolution occurs on the proxy server.
index
editThe index root name to write events to. The default is the Beat name. For
example "filebeat"
generates "[filebeat-]8.15.2-YYYY.MM.DD"
indices (for example, "filebeat-8.15.2-2017.04.26"
).
This parameter’s value will be assigned to the metadata.beat
field. It
can then be accessed in Logstash’s output section as %{[@metadata][beat]}
.
ssl
editConfiguration options for SSL parameters like the root CA for Logstash connections. See SSL for more information. To use SSL, you must also configure the Beats input plugin for Logstash to use SSL/TLS.
timeout
editThe number of seconds to wait for responses from the Logstash server before timing out. The default is 30 (seconds).
max_retries
editFilebeat ignores the max_retries
setting and retries indefinitely.
bulk_max_size
editThe maximum number of events to bulk in a single Logstash request. The default is 2048.
Events can be collected into batches. Filebeat will split batches read from the queue which are
larger than bulk_max_size
into multiple batches.
Specifying a larger batch size can improve performance by lowering the overhead of sending events. However big batch sizes can also increase processing times, which might result in API errors, killed connections, timed-out publishing requests, and, ultimately, lower throughput.
Setting bulk_max_size
to values less than or equal to 0 disables the
splitting of batches. When splitting is disabled, the queue decides on the
number of events to be contained in a batch.
slow_start
editIf enabled, only a subset of events in a batch of events is transferred per transaction.
The number of events to be sent increases up to bulk_max_size
if no error is encountered.
On error, the number of events per transaction is reduced again.
The default is false
.
backoff.init
editThe number of seconds to wait before trying to reconnect to Logstash after
a network error. After waiting backoff.init
seconds, Filebeat tries to
reconnect. If the attempt fails, the backoff timer is increased exponentially up
to backoff.max
. After a successful connection, the backoff timer is reset. The
default is 1s.
backoff.max
editThe maximum number of seconds to wait before attempting to connect to Logstash after a network error. The default is 60s.