WARNING: Version 5.0 of Elasticsearch has passed its EOL date.
This documentation is no longer being maintained and may be removed. If you are running this version, we strongly advise you to upgrade. For the latest information, see the current release documentation.
Configuring Elasticsearch
editConfiguring Elasticsearch
editElasticsearch ships with good defaults and requires very little configuration. Most settings can be changed on a running cluster using the Cluster Update Settings API.
The configuration files should contain settings which are node-specific (such
as node.name
and paths), or settings which a node requires in order to be
able to join a cluster, such as cluster.name
and network.host
.
Config file location
editElasticsearch has two configuration files:
-
elasticsearch.yml
for configuring Elasticsearch, and -
log4j2.properties
for configuring Elasticsearch logging.
These files are located in the config directory, whose location defaults to
$ES_HOME/config/
. The Debian and RPM packages set the config directory
location to /etc/elasticsearch/
.
The location of the config directory can be changed with the path.conf
setting, as follows:
./bin/elasticsearch -Epath.conf=/path/to/my/config/
Config file format
editThe configuration format is YAML. Here is an example of changing the path of the data and logs directories:
path: data: /var/lib/elasticsearch logs: /var/log/elasticsearch
Settings can also be flattened as follows:
path.data: /var/lib/elasticsearch path.logs: /var/log/elasticsearch
Environment variable substitution
editEnvironment variables referenced with the ${...}
notation within the
configuration file will be replaced with the value of the environment
variable, for instance:
node.name: ${HOSTNAME} network.host: ${ES_NETWORK_HOST}
Prompting for settings
editFor settings that you do not wish to store in the configuration file, you can
use the value ${prompt.text}
or ${prompt.secret}
and start Elasticsearch
in the foreground. ${prompt.secret}
has echoing disabled so that the value
entered will not be shown in your terminal; ${prompt.text}
will allow you to
see the value as you type it in. For example:
node: name: ${prompt.text}
When starting Elasticsearch, you will be prompted to enter the actual value like so:
Enter value for [node.name]:
Elasticsearch will not start if ${prompt.text}
or ${prompt.secret}
is used in the settings and the process is run as a service or in the background.
Setting default settings
editNew default settings may be specified on the command line using the
default.
prefix. This will specify a value that will be used by
default unless another value is specified in the config file.
For instance, if Elasticsearch is started as follows:
./bin/elasticsearch -Edefault.node.name=My_Node
the value for node.name
will be My_Node
, unless it is overwritten on the
command line with es.node.name
or in the config file with node.name
.
Logging configuration
editElasticsearch uses Log4j 2 for
logging. Log4j 2 can be configured using the log4j2.properties
file. Elasticsearch exposes a single property ${sys:es.logs}
that can be
referenced in the configuration file to determine the location of the log files;
this will resolve to a prefix for the Elasticsearch log file at runtime.
For example, if your log directory (path.logs
) is /var/log/elasticsearch
and
your cluster is named production
then ${sys:es.logs}
will resolve to
/var/log/elasticsearch/production
.
appender.rolling.type = RollingFile appender.rolling.name = rolling appender.rolling.fileName = ${sys:es.logs}.log appender.rolling.layout.type = PatternLayout appender.rolling.layout.pattern = [%d{ISO8601}][%-5p][%-25c] %.10000m%n appender.rolling.filePattern = ${sys:es.logs}-%d{yyyy-MM-dd}.log appender.rolling.policies.type = Policies appender.rolling.policies.time.type = TimeBasedTriggeringPolicy appender.rolling.policies.time.interval = 1 appender.rolling.policies.time.modulate = true
Configure the |
|
Log to |
|
Roll logs to |
|
Using a time-based roll policy |
|
Roll logs on a daily basis |
|
Align rolls on the day boundary (as opposed to rolling every twenty-four hours) |
If you append .gz
or .zip
to appender.rolling.filePattern
, then the logs
will be compressed as they are rolled.
Multiple configuration files can be loaded (in which case they will get merged)
as long as they are named log4j2.properties
and have the Elasticsearch config
directory as an ancestor; this is useful for plugins that expose additional
loggers. The logger section contains the java packages and their corresponding
log level. The appender section contains the destinations for the logs.
Extensive information on how to customize logging and all the supported
appenders can be found on the
Log4j
documentation.
Deprecation logging
editIn addition to regular logging, Elasticsearch allows you to enable logging of deprecated actions. For example this allows you to determine early, if you need to migrate certain functionality in the future. By default, deprecation logging is enabled at the WARN level, the level at which all deprecation log messages will be emitted.
logger.deprecation.level = warn
This will create a daily rolling deprecation log file in your log directory. Check this file regularly, especially when you intend to upgrade to a new major version.
The default logging configuration has set the roll policy for the deprecation logs to roll and compress after 1 GB, and to preserve a maximum of five log files (four rolled logs, and the active log).
You can disable it in the config/log4j2.properties
file by setting the deprecation
log level to error
.