WARNING: Version 5.4 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.
Elasticsearch is also available as a Docker image. The image is built with X-Pack and uses centos:7 as the base image. The source code can be found on GitHub.
X-Pack is preinstalled in this image.
Please take a few minutes to familiarize yourself with
X-Pack Security and how to change
default passwords. The default password for the elastic
user is changeme
.
X-Pack includes a trial license for 30 days. After that, you can obtain one of the available subscriptions or disable Security. The Basic license is free and includes the Monitoring extension.
Obtaining for Docker is as simple as issuing a docker pull
command
against the Elastic Docker registry.
The Docker image can be retrieved with the following command:
docker pull docker.elastic.co/elasticsearch/elasticsearch:5.4.3
Elasticsearch can be quickly started for development or testing use with the following command:
docker run -p 9200:9200 -p 9300:9300 -e "discovery.type=single-node" docker.elastic.co/elasticsearch/elasticsearch:5.4.3
The vm_max_map_count
kernel setting needs to be set to at least 262144
for
production use. Depending on your platform:
-
Linux
The
vm_map_max_count
setting should be set permanently in /etc/sysctl.conf:$ grep vm.max_map_count /etc/sysctl.conf vm.max_map_count=262144
To apply the setting on a live system type:
sysctl -w vm.max_map_count=262144
-
OSX with Docker for Mac
The
vm_max_map_count
setting must be set within the xhyve virtual machine:$ screen ~/Library/Containers/com.docker.docker/Data/com.docker.driver.amd64-linux/tty
Log in with root and no password. Then configure the
sysctl
setting as you would for Linux:sysctl -w vm.max_map_count=262144
-
OSX with Docker Toolbox
The
vm_max_map_count
setting must be set via docker-machine:docker-machine ssh sudo sysctl -w vm.max_map_count=262144
The following example brings up a cluster comprising two Elasticsearch nodes.
To bring up the cluster, use the
docker-compose.yml
and just type:
docker-compose up
docker-compose
is not pre-installed with Docker on Linux.
Instructions for installing it can be found on the
docker-compose webpage.
The node elasticsearch1
listens on localhost:9200
while elasticsearch2
talks to elasticsearch1
over a Docker network.
This example also uses
Docker named volumes,
called esdata1
and esdata2
which will be created if not already present.
version: '2' services: elasticsearch1: image: docker.elastic.co/elasticsearch/elasticsearch:5.4.3 container_name: elasticsearch1 environment: - cluster.name=docker-cluster - bootstrap.memory_lock=true - "ES_JAVA_OPTS=-Xms512m -Xmx512m" ulimits: memlock: soft: -1 hard: -1 mem_limit: 1g volumes: - esdata1:/usr/share/elasticsearch/data ports: - 9200:9200 networks: - esnet elasticsearch2: image: docker.elastic.co/elasticsearch/elasticsearch:5.4.3 environment: - cluster.name=docker-cluster - bootstrap.memory_lock=true - "ES_JAVA_OPTS=-Xms512m -Xmx512m" - "discovery.zen.ping.unicast.hosts=elasticsearch1" ulimits: memlock: soft: -1 hard: -1 mem_limit: 1g volumes: - esdata2:/usr/share/elasticsearch/data networks: - esnet volumes: esdata1: driver: local esdata2: driver: local networks: esnet:
To stop the cluster, type docker-compose down
. Data volumes will persist, so
it’s possible to start the cluster again with the same data using
docker-compose up
. To destroy the cluster and the data volumes just type
docker-compose down -v
.
curl -u elastic http://127.0.0.1:9200/_cat/health Enter host password for user 'elastic': 1472225929 15:38:49 docker-cluster green 2 2 4 2 0 0 0 0 - 100.0%
Log messages go to the console and are handled by the configured Docker logging
driver. By default you can access logs with docker logs
.
Elasticsearch loads its configuration from files under /usr/share/elasticsearch/config/
.
These configuration files are documented in Configuring Elasticsearch and Setting JVM options.
The image offers several methods for configuring Elasticsearch settings with the
conventional approach being to provide customized files, that is to say,
elasticsearch.yml
. It’s also possible to use environment variables to set
options:
For example, to define the cluster name with docker run
you can pass
-e "cluster.name=mynewclustername"
. Double quotes are required.
Create your custom config file and mount this over the image’s corresponding
file. For example, bind-mounting a custom_elasticsearch.yml
with docker run
can be accomplished with the parameter:
-v full_path_to/custom_elasticsearch.yml:/usr/share/elasticsearch/config/elasticsearch.yml
The container runs Elasticsearch as user elasticsearch
using uid:gid 1000:1000
.
Bind mounted host directories and files, such as custom_elasticsearch.yml
above, need to be accessible by this user. For the
data and log dirs,
such as /usr/share/elasticsearch/data
, write access is required as well.
In some environments, it may make more sense to prepare a custom image
containing your configuration. A Dockerfile
to achieve this may be as simple
as:
FROM docker.elastic.co/elasticsearch/elasticsearch:5.4.3 ADD elasticsearch.yml /usr/share/elasticsearch/config/ USER root RUN chown elasticsearch:elasticsearch config/elasticsearch.yml USER elasticsearch
You could then build and try the image with something like:
docker build --tag=elasticsearch-custom . docker run -ti -v /usr/share/elasticsearch/data elasticsearch-custom
D. Override the image’s default CMD
Options can be passed as command-line options to the Elasticsearch process by overriding the default command for the image. For example:
docker run <various parameters> bin/elasticsearch -Ecluster.name=mynewclustername
We have collected a number of best practices for production use.
Any Docker parameters mentioned below assume the use of docker run
.
-
Elasticsearch runs inside the container as user
elasticsearch
using uid:gid1000:1000
. If you are bind-mounting a local directory or file, ensure it is readable by this user, while the data and log dirs additionally require write access. -
It is important to ensure increased ulimits for nofile and nproc are available for the Elasticsearch containers. Verify the init system for the Docker daemon is already setting those to acceptable values and, if needed, adjust them in the Daemon, or override them per container, for example using
docker run
:--ulimit nofile=65536:65536
One way of checking the Docker daemon defaults for the aforementioned ulimits is by running:
docker run --rm centos:7 /bin/bash -c 'ulimit -Hn && ulimit -Sn && ulimit -Hu && ulimit -Su'
-
Swapping needs to be disabled for performance and node stability. This can be achieved through any of the methods mentioned in the Elasticsearch docs. If you opt for the
bootstrap.memory_lock: true
approach, apart from defining it through any of the configuration methods, you will additionally need thememlock: true
ulimit, either defined in the Docker Daemon or specifically set for the container. This has been demonstrated earlier in the docker-compose.yml, or usingdocker run
:-e "bootstrap_memory_lock=true" --ulimit memlock=-1:-1
-
The image exposes
TCP ports 9200 and 9300. For clusters it is recommended to randomize the
published ports with
--publish-all
, unless you are pinning one container per host. -
Use the
ES_JAVA_OPTS
environment variable to set heap size. For example, to use 16GB, use-e ES_JAVA_OPTS="-Xms16g -Xmx16g"
withdocker run
. It is also recommended to set a memory limit for the container. -
Pin your deployments to a specific version of the Elasticsearch Docker image. For
example,
docker.elastic.co/elasticsearch/elasticsearch:5.4.3
. -
Always use a volume bound on
/usr/share/elasticsearch/data
, as shown in the production example, for the following reasons:- The data of your elasticsearch node won’t be lost if the container is killed
- Elasticsearch is I/O sensitive and the Docker storage driver is not ideal for fast I/O
- It allows the use of advanced Docker volume plugins
-
If you are using the devicemapper storage driver (default on at least RedHat
(rpm) based distributions) make sure you are not using the default
loop-lvm
mode. Configure docker-engine to use direct-lvm instead. - Consider centralizing your logs by using a different logging driver. Also note that the default json-file logging driver is not ideally suited for production use.
You now have a test Elasticsearch environment set up. Before you start serious development or go into production with Elasticsearch, you must do some additional setup:
- Learn how to configure Elasticsearch.
- Configure important Elasticsearch settings.
- Configure important system settings.