Elasticsearch Config

elasticsearch.sh

#!/bin/sh
set -e;

function es_uninstall {
  yum remove java-1.8.0-amazon-corretto -y
  rpm -e `rpm -qa elasticsearch`
}

function es_install {
  # Set Environment Variables
  export IMDSv2_TOKEN=`curl -s -X PUT "http://169.254.169.254/latest/api/token" -H "X-aws-ec2-metadata-token-ttl-seconds: 21600"`;
  export AWS_REGION=`curl -s -H "X-aws-ec2-metadata-token: ${IMDSv2_TOKEN}" http://169.254.169.254/latest/meta-data/placement/region/`;
  export AWS_AVAILABILITY_ZONE=`curl -s -H "X-aws-ec2-metadata-token: ${IMDSv2_TOKEN}" http://169.254.169.254/latest/meta-data/placement/availability-zone/`;

  if [[ -z "$AWS_REGION" || -z "$AWS_AVAILABILITY_ZONE" ]]; then
    echo "Failed to fetch AWS Region and Availability Zone from IMDSv2."
    exit 1
  fi

  # Install dependency
  yum install java-1.8.0-amazon-corretto -y

  # Download and extract Elasticsearch
  curl -s -o elasticsearch.rpm "https://download.elastic.co/elasticsearch/release/org/elasticsearch/distribution/rpm/elasticsearch/2.4.6/elasticsearch-2.4.6.rpm"
  ELASTICSEARCH_SHA1=`curl -s https://download.elastic.co/elasticsearch/release/org/elasticsearch/distribution/rpm/elasticsearch/2.4.6/elasticsearch-2.4.6.rpm.sha1` &&
  echo "$ELASTICSEARCH_SHA1 elasticsearch.rpm" | sha1sum -c -
  rpm -i elasticsearch.rpm
  rm -f elasticsearch.rpm

  export ES_CFG=/etc/elasticsearch/elasticsearch.yml
  # Pull and inject AZ variables into Elasticsearch config
  curl -s -o $ES_CFG https://gist.githubusercontent.com/CameronHall/c8e58d10dc513a6eb7bdd7d337dfb318/raw/elasticsearch.yml
  sed -i "s/{{aws_region}}/$AWS_REGION/g" $ES_CFG
  sed -i "s/{{aws_availability_zone}}/$AWS_AVAILABILITY_ZONE/g" $ES_CFG
  sed -i 's/{{cluster_name}}/absinthe-elasticsearch/g' $ES_CFG
  
  # Install Elasticsearch AWS plugin
  yes | /usr/share/elasticsearch/bin/plugin install cloud-aws

  # Set the ES_HEAP_SIZE to 50% of the system memory and write to /etc/sysconfig/elasticsearch
  memory_info=$(free -m)
  total_memory=$(echo "$memory_info" | awk 'FNR == 2 {print $2}')
  echo "ES_HEAP_SIZE=$((total_memory / 2))m" >> /etc/sysconfig/elasticsearch

  # Update PID path for systemctl
  systemctl enable elasticsearch.service
  sed -i 's/\/var\/run/\/run/g' /etc/systemd/system/multi-user.target.wants/elasticsearch.service
  systemctl daemon-reload
  systemctl restart elasticsearch
}


case "$1" in

  install)
    es_install
    ;;

  uninstall)
    es_uninstall
    ;;

  *)
    echo "This script will install and configure Elasticsearch 2.4
One of the following arguments must be provided; 
    - install
    - uninstall
"
    ;;
esac

elasticsearch.yml

---
node.awszone: {{aws_availability_zone}}
index.number_of_replicas: 2
cloud:
  aws:
    region: {{aws_region}}
cluster:
  name: {{cluster_name}}
  routing.allocation.awareness.attributes: awszone
discovery:
  ec2:
    tag:
      role: search
  type: ec2
  zen:
    minimum_master_nodes: 3
    ping:
      multicast:
        enabled: false
path:
  data: /var/lib/elasticsearch
network.host: 0.0.0.0
http.port: 9200
plugin:
  mandatory: cloud-aws