Elasticsearch single-node cluster

This document will explain how to install the Elastic Stack components in a single-node cluster.

Note

You need root user privileges to run all the commands described below.

Installing Elasticsearch

Elasticsearch is a highly scalable full-text search and analytics engine.

Installing prerequisites

Some extra packages are needed for the installation, such as curl or unzip, that will be used in further steps:

Install all the necessary packages:

# yum install zip unzip curl

Adding the Elastic Stack repository

  1. Import the GPG key:

    # rpm --import https://artifacts.elastic.co/GPG-KEY-elasticsearch
    
  2. Add the repository:

    # cat > /etc/yum.repos.d/elastic.repo << EOF
    [elasticsearch-7.x]
    name=Elasticsearch repository for 7.x packages
    baseurl=https://artifacts.elastic.co/packages/7.x/yum
    gpgcheck=1
    gpgkey=https://artifacts.elastic.co/GPG-KEY-elasticsearch
    enabled=1
    autorefresh=1
    type=rpm-md
    EOF
    

Elasticsearch installation and configuration

  1. Install the Elasticsearch package:

    # yum install elasticsearch-7.17.9
    
  2. Once Elasticsearch is installed, it can be configured by downloading the file /etc/elasticsearch/elasticsearch.yml:

    # curl -so /etc/elasticsearch/elasticsearch.yml https://packages.wazuh.com/4.4/tpl/elastic-basic/elasticsearch.yml
    

Certificates creation and deployment

  1. The number of Wazuh servers to be implemented will determine the next step. Select Wazuh single-node cluster, if there is only one Wazuh server, or Wazuh multi-node cluster in case there are two or more Wazuh servers.

    The instances file can be created /usr/share/elasticsearch/instances.yml as follows:

    cat > /usr/share/elasticsearch/instances.yml <<\EOF
    instances:
    - name: "elasticsearch"
      ip:
      - "10.0.0.2"
    - name: "filebeat"
      ip:
      - "10.0.0.3"
    - name: "kibana"
      ip:
      - "10.0.0.4"
    EOF
    

    Every name section corresponds to one host in the Wazuh Server - Elastic Stack environment. In this example, the file describes:

    • An elasticsearch instance with IP address 10.0.0.2.

    • A filebeat instance with IP address 10.0.0.3 corresponding to a single-node Wazuh cluster.

    • A kibana instance with IP address 10.0.0.4. If Kibana will be installed in the same server as Elasticsearch, the same IP address may be used.

    Replace the IPs with the corresponding addresses for each instance in your environment.

    Create the certificates using the elasticsearch-certutil tool:

    # /usr/share/elasticsearch/bin/elasticsearch-certutil cert ca --pem --in instances.yml --keep-ca-key --out ~/certs.zip
    

    The resulting file certs.zip contains a directory for each instance included in instances.yml. Each directory contains a certificate and a private key necessary to secure communications.

  2. Copy ~/certs.zip to all the servers of the distributed deployment. This can be done by using, for example, scp.

  3. The next step is to create the directory /etc/elasticsearch/certs, and then copy the certificate authorities, the certificate and key there:

    # unzip ~/certs.zip -d ~/certs
    # mkdir /etc/elasticsearch/certs/ca -p
    # cp -R ~/certs/ca/ ~/certs/elasticsearch/* /etc/elasticsearch/certs/
    # chown -R elasticsearch: /etc/elasticsearch/certs
    # chmod -R 500 /etc/elasticsearch/certs
    # chmod 400 /etc/elasticsearch/certs/ca/ca.* /etc/elasticsearch/certs/elasticsearch.*
    # rm -rf ~/certs/
    
  4. If you are going to install Kibana in this node, keep the certificates file. Otherwise, if the file has been copied already to all the instances of the distributed deployment, remove it to increase security rm -f ~/certs.zip.

  5. Enable and start the Elasticsearch service:

    # systemctl daemon-reload
    # systemctl enable elasticsearch
    # systemctl start elasticsearch
    
  6. Generate credentials for all the Elastic Stack pre-built roles and users:

    # /usr/share/elasticsearch/bin/elasticsearch-setup-passwords auto
    

    The command above will prompt an output like this. Save the password of the elastic user for further steps:

    Changed password for user apm_system
    PASSWORD apm_system = lLPZhZkB6oUOzzCrkLSF
    
    Changed password for user kibana_system
    PASSWORD kibana_system = TaLqVOnSoqKTYLIU0vDn
    
    Changed password for user kibana
    PASSWORD kibana = TaLqVOvXoqKTYLIU0vDn
    
    Changed password for user logstash_system
    PASSWORD logstash_system = UtuDv2tWkXGYL83v9kWA
    
    Changed password for user beats_system
    PASSWORD beats_system = qZcbvCslafMpoEOrE9Ob
    
    Changed password for user remote_monitoring_user
    PASSWORD remote_monitoring_user = LzJpQiSylncmCU2GLBTS
    
    Changed password for user elastic
    PASSWORD elastic = AN4UeQGA7HGl5iHpMla7
    

Disabling repositories

This installation guide describes how to install and configure Wazuh and Elastic Stack by first configuring their repositories.

With each new release of Wazuh or Elastic Stack, the development team at Wazuh thoroughly tests the compatibility of each component and performs necessary adjustments before releasing a new Wazuh Kibana plugin.

We recommend disabling the repositories so that the individual packages will not be updated unintentionally, which could potentially lead to having a version of the Elastic Stack for which the Wazuh integration has not been released yet.

# sed -i "s/^enabled=1/enabled=0/" /etc/yum.repos.d/elastic.repo

To uninstall Elasticsearch, visit the uninstalling section.

Next steps

The next step is the installation of the Wazuh server, select the cluster mode: