Elasticsearch

Hardware requirements

CPU

At least 2 cores.

Memory

At least 32GB of RAM as Elasticsearch will allocate half of the available memory for its own usage. Elasticsearch recommends no more that 64GB of RAM per node in the Elasticsearch cluster.

Disk

The recommended size is at least 1.5GB of disk per millions of jobs.

In case OKA is configured to monitor your cloud consumption using CloudSHaper, we recommend to provision 2GB of disk per millions of entries.

Installation

Since 2021 Elasticsearch has moved to a single licensing model and versions supported by OKA can be found through the following link:

• Elastic past version

For more info look at:

• https://www.elastic.co/guide/en/elasticsearch/reference/current/install-elasticsearch.html

Example:

Debian 11Amazon Linux 2/2023, RHEL 7/8/9, Rocky Linux 8/9

Elasticsearch version 7.17.13:

wget https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-7.17.13-amd64.deb
dpkg -i elasticsearch-7.17.13-amd64.deb

HowTo

• Configuration:

  It is recommended to have a look at this documentation prior to starting your service:

  • https://www.elastic.co/guide/en/elasticsearch/reference/current/advanced-configuration.html

  Make sure to configure the JVM heap size correctly. To do so, edit the JVM configuration (/etc/elasticsearch/jvm.options) and set the total heap space either to:

  • Half of the node’s total memory. For example, if the total memory is 32GB, set -Xms16g and -Xmx16g.

  • Or comment those 2 lines to let Elasticsearch manage the heap space (see set-jvm-heap-size).

• Start elasticsearch service:

  sudo /bin/systemctl enable elasticsearch.service
  sudo systemctl start elasticsearch.service
  

• Test it using curl:

  sudo apt-get update; sudo apt-get install -y curl
  curl -X GET "host:port/_cat/health?v&pretty"
  

• Optional - Add a proxy:

  If on a container or a virtual machine you might want to create a proxy in order to access your db from somewhere else. See the nginx page.

  Create a dedicated conf file for elasticsearch:

  sudo vim /etc/nginx/conf.d/elastic.conf
  server {
          listen 8080;
          location / {
              proxy_pass http://host:port;
          }
      }
  

  You might also want to edit the maximum size allowed for the request handled by nginx:

  • https://nginx.org/en/docs/http/ngx_http_core_module.html#client_max_body_size

  Restart your services:

  sudo systemctl restart elasticsearch.service
  sudo service nginx restart