Building an ELK Stack with Docker Compose

These files can be used to create a generic ELK stack using Docker Compose. This can be helpful for testing, local development, and POC work. Looking for a fast setup and teardown makes Docker perfect for this use case.

Prerequisites

This assumes that you have git and docker desktop or docker engine with docker-compose installed. For this scenario, we will be using Docker Desktop.

File Structure

This is a simple file structure that will build Elasticsearch, Logstash, and Kibana from the docker-compose file, with additional configuration for Logstash in a yml file. This basic structure can be expanded to add additional components such as Filebeat, Metricbeat, etc.

• .env
• docker-compose.yml
• logstash.conf

Environment File

The .env file is used to define variables that will be passed to docker-compose. My sample file is below and can be customized as needed.

# Password for the 'elastic' user (at least 6 characters)
ELASTIC_PASSWORD=changeme

# Password for the 'kibana_system' user (at least 6 characters)
KIBANA_PASSWORD=changeme

# Version of Elastic products
STACK_VERSION=8.9.1

# Set the cluster name
CLUSTER_NAME=docker-cluster

# Set to 'basic' or 'trial' to automatically start the 30-day trial
LICENSE=basic

# Port to expose Elasticsearch HTTP API to the host
ES_PORT=9200

# Port to expose Kibana to the host
KIBANA_PORT=5601

# Increase or decrease based on the available host memory (in bytes)
MEM_LIMIT=1073741824

The default passwords of "changeme" should always be changed, regardless of whether or not this is for a testing environment.

The STACK_VERSION variable is used to reference in the docker-compose.yml file. This helps ensure you are using the same version for all the components, and is also required because the Elastic Stack images do not support the :latest tag.

We are also specifying port numbers and memory limits to be used.

Containers

An initial setup container is required as version 8.0+ of Elasticsearch has security enabled by default. We can use this container to create the necessary certificates.

setup Container

The setup container is started first and will save the generated certificates to the certs volume, which makes them accessible to the other containers we are building. It will also pass variables to the Elasticsearch container for cluster configuration.

version: "3.8"

services:
  setup:
    image: docker.elastic.co/elasticsearch/elasticsearch:${STACK_VERSION}
    volumes:
      - certs:/usr/share/elasticsearch/config/certs
    user: "0"
    command: >
      bash -c '
        if [ x${ELASTIC_PASSWORD} == x ]; then
          echo "Set the ELASTIC_PASSWORD environment variable in the .env file";
          exit 1;
        elif [ x${KIBANA_PASSWORD} == x ]; then
          echo "Set the KIBANA_PASSWORD environment variable in the .env file";
          exit 1;
        fi;
        if [ ! -f config/certs/ca.zip ]; then
          echo "Creating CA";
          bin/elasticsearch-certutil ca --silent --pem -out config/certs/ca.zip;
          unzip config/certs/ca.zip -d config/certs;
        fi;
        if [ ! -f config/certs/certs.zip ]; then
          echo "Creating certs";
          echo -ne \
          "instances:\n"\
          "  - name: es01\n"\
          "    dns:\n"\
          "      - es01\n"\
          "      - localhost\n"\
          "    ip:\n"\
          "      - 127.0.0.1\n"\
          "  - name: kibana\n"\
          "    dns:\n"\
          "      - kibana\n"\
          "      - localhost\n"\
          "    ip:\n"\
          "      - 127.0.0.1\n"\
          > config/certs/instances.yml;
          bin/elasticsearch-certutil cert --silent --pem -out config/certs/certs.zip --in config/certs/instances.yml --ca-cert config/certs/ca/ca.crt --ca-key config/certs/ca/ca.key;
          unzip config/certs/certs.zip -d config/certs;
        fi;
        echo "Setting file permissions"
        chown -R root:root config/certs;
        find . -type d -exec chmod 750 \{\} \;;
        find . -type f -exec chmod 640 \{\} \;;
        echo "Waiting for Elasticsearch availability";
        until curl -s --cacert config/certs/ca/ca.crt https://es01:9200 | grep -q "missing authentication credentials"; do sleep 30; done;
        echo "Setting kibana_system password";
        until curl -s -X POST --cacert config/certs/ca/ca.crt -u "elastic:${ELASTIC_PASSWORD}" -H "Content-Type: application/json" https://es01:9200/_security/user/kibana_system/_password -d "{\"password\":\"${KIBANA_PASSWORD}\"}" | grep -q "^{}"; do sleep 10; done;
        echo "All done!";
      '
    healthcheck:
      test: ["CMD-SHELL", "[ -f config/certs/es01/es01.crt ]"]
      interval: 1s
      timeout: 5s
      retries: 120

es01 Container

This container builds a single-node Elasticsearch cluster.

  es01:
    depends_on:
      setup:
        condition: service_healthy
    image: docker.elastic.co/elasticsearch/elasticsearch:${STACK_VERSION}
    volumes:
      - certs:/usr/share/elasticsearch/config/certs
      - esdata01:/usr/share/elasticsearch/data
    ports:
      - ${ES_PORT}:9200
    environment:
      - node.name=es01
      - cluster.name=${CLUSTER_NAME}
      - discovery.type=single-node
      - ELASTIC_PASSWORD=${ELASTIC_PASSWORD}
      - bootstrap.memory_lock=true
      - xpack.security.enabled=true
      - xpack.security.http.ssl.enabled=true
      - xpack.security.http.ssl.key=certs/es01/es01.key
      - xpack.security.http.ssl.certificate=certs/es01/es01.crt
      - xpack.security.http.ssl.certificate_authorities=certs/ca/ca.crt
      - xpack.security.transport.ssl.enabled=true
      - xpack.security.transport.ssl.key=certs/es01/es01.key
      - xpack.security.transport.ssl.certificate=certs/es01/es01.crt
      - xpack.security.transport.ssl.certificate_authorities=certs/ca/ca.crt
      - xpack.security.transport.ssl.verification_mode=certificate
      - xpack.license.self_generated.type=${LICENSE}
    mem_limit: ${MEM_LIMIT}
    ulimits:
      memlock:
        soft: -1
        hard: -1
    healthcheck:
      test:
        [
          "CMD-SHELL",
          "curl -s --cacert config/certs/ca/ca.crt https://localhost:9200 | grep -q 'missing authentication credentials'",
        ]
      interval: 10s
      timeout: 10s
      retries: 120

kibana Container

The Kibana container is dependent upon the Elasticsearch container running in a healthy state, and utilizes the certificates created during setup.

  kibana:
    depends_on:
      es01:
        condition: service_healthy
    image: docker.elastic.co/kibana/kibana:${STACK_VERSION}
    volumes:
      - certs:/usr/share/kibana/config/certs
      - kibanadata:/usr/share/kibana/data
    ports:
      - ${KIBANA_PORT}:5601
    environment:
      - SERVERNAME=kibana
      - ELASTICSEARCH_HOSTS=https://es01:9200
      - ELASTICSEARCH_USERNAME=kibana_system
      - ELASTICSEARCH_PASSWORD=${KIBANA_PASSWORD}
      - ELASTICSEARCH_SSL_CERTIFICATEAUTHORITIES=config/certs/ca/ca.crt
    mem_limit: ${MEM_LIMIT}
    healthcheck:
      test:
        [
          "CMD-SHELL",
          "curl -s -I http://localhost:5601 | grep -q 'HTTP/1.1 302 Found'",
        ]
      interval: 10s
      timeout: 10s
      retries: 120

logstash01 Container

Logstash is the final container to bring online, and has some additional configuration in the logstash.conf file.

  logstash01:
    depends_on:
      es01:
        condition: service_healthy
      kibana:
        condition: service_healthy
    image: docker.elastic.co/logstash/logstash:${STACK_VERSION}
    labels:
      co.elastic.logs/module: logstash
    user: root
    volumes:
      - certs:/usr/share/logstash/certs
      - logstashdata01:/usr/share/logstash/data
      - "./logstash_ingest_data/:/usr/share/logstash/ingest_data/"
      - "./logstash.conf:/usr/share/logstash/pipeline/logstash.conf:ro"
    environment:
      - xpack.monitoring.enabled=false
      - ELASTIC_USER=elastic
      - ELASTIC_PASSWORD=${ELASTIC_PASSWORD}
      - ELASTIC_HOSTS=https://es01:9200

Building the Containers using Docker Compose

Git clone the repository by running the following commands, one at a time:

git clone https://github.com/mnyethecyberguy/docker-elk.git

and then

cd docker-elk

Start the containers

docker compose up

Teardown

To destroy the environment, including containers and volumes, specify the -v option:

docker compose down -v

Configuration Considerations

Additional References

https://docs.docker.com/engine/reference/commandline/compose/#child-commands