openstack-ansible-ops/elk_metrics_6x/roles/elastic_data_hosts/vars/data-node-variables.yml

---
# Copyright 2018, Rackspace US, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# storage node count is equal to the cluster size
storage_node_count: "{{ groups['elastic-logstash'] | length }}"

# the elasticserch cluster elects one master from all those which are marked as master-eligible
# 1 node cluster can only have one master
# 2 node clusters have 1 master-eligable nodes to avoid split-brain
# 3 node clusters have 3 master-eligable nodes
# >3 node clusters have (nodes // 2) eligable masters rounded up to the next odd number
master_node_count: |-
  {% set masters = 0 %}
  {% if (storage_node_count | int) < 3 %}
  {%   set masters = 1 %}
  {% elif (storage_node_count | int) == 3 %}
  {%   set masters = 3 %}
  {% else %}
  {%   set masters = (storage_node_count | int ) // 2 %}
  {%   if ((masters | int) % 2 == 0) %}
  {%     set masters = (masters | int) + 1 %}
  {%   endif %}
  {% endif %}
  {{ masters }}

# Assign node roles
# the first 'master_node_count' hosts in groups['elastic-logstash'] become master-eligible nodes
# the first 'master_node_count' and subsequent alternate hosts in groups['elastic-logstash'] becomes data nodes
data_nodes: "{{ (groups['elastic-logstash'][:master_node_count | int] + groups['elastic-logstash'][master_node_count | int::2]) }}"
master_nodes: "{{ groups['elastic-logstash'][:master_node_count | int] }}"
coordination_nodes: >-
  {{
    (groups['kibana'] | map('extract', hostvars, 'ansible_host') | list)
      | map('regex_replace', '(.*)' ,'\1:' ~ elastic_port)
      | list
  }}
zen_nodes: >-
  {{
    (groups['elastic-logstash'] | union(groups['kibana'])) | map('extract', hostvars, 'ansible_host') | list | shuffle(seed=inventory_hostname)
  }}
elasticserch_interface_speed: |-
  {% set default_interface_fact = hostvars[inventory_hostname]['ansible_' + (elastic_data_interface | replace('-', '_'))] %}
  {% set speeds = [] %}
  {% if default_interface_fact['type'] == 'bridge' %}
  {%   for interface in default_interface_fact['interfaces'] %}
  {%     set interface_fact = hostvars[inventory_hostname]['ansible_' + (interface | replace('-', '_'))] %}
  {%     if 'speed' in interface_fact %}
  {%       set speed = (interface_fact['speed'] | default(1000)) | string %}
  {%       if speed == "-1" %}
  {%         set _ = speeds.append(1000) %}
  {%       else %}
  {%         set _ = speeds.append(speed | int) %}
  {%       endif %}
  {%       if 'module' in interface_fact %}
  {%         set _ = speeds.append((interface_fact['speed'] | default(1000)) | int) %}
  {%       else %}
  {%         set _ = speeds.append(1000) %}
  {%       endif %}
  {%     endif %}
  {%   endfor %}
  {% else %}
  {%   if ('module' in default_interface_fact) or (default_interface_fact['type'] == 'bond') %}
  {%     set speed = (default_interface_fact['speed'] | default(1000)) | string %}
  {%     if speed == "-1" %}
  {%       set _ = speeds.append(1000) %}
  {%     else %}
  {%       set _ = speeds.append(speed | int) %}
  {%     endif %}
  {%   else %}
  {%     set _ = speeds.append(1000) %}
  {%   endif %}
  {% endif %}
  {% set interface_speed = ((speeds | min) * 0.20) | int %}
  {{ ((interface_speed | int) > 750) | ternary(750, interface_speed) }}
elasticsearch_data_node_details: >-
  {{
    (data_nodes | map('extract', hostvars, 'ansible_host') | list) | map('regex_replace', '(.*)' ,'\1:' ~ elastic_port) | list
  }}
logstash_data_node_details: >-
  {{
    (data_nodes | map('extract', hostvars, 'ansible_host') | list) | map('regex_replace', '(.*)' ,'\1:' ~ logstash_beat_input_port) | list
  }}

# based on the assignment of roles to hosts, set per host booleans
master_node: "{{ (inventory_hostname in master_nodes) | ternary(true, false) }}"
data_node: "{{ (inventory_hostname in data_nodes) | ternary(true, false) }}"

elastic_processors_floor: "{{ ((ansible_processor_count | int) - 1) }}"
elastic_processors_floor_set: "{{ ((elastic_processors_floor | int) > 0) | ternary(elastic_processors_floor, 1) }}"
elastic_thread_pool_size: "{{ ((ansible_processor_count | int) >= 24) | ternary(23, elastic_processors_floor_set) }}"

# Set a data node facts. The data nodes, in the case of elasticsearch are also
# ingest nodes.
elasticsearch_number_of_replicas: "{{ ((data_nodes | length) > 2) | ternary('2', ((data_nodes | length) > 1) | ternary('1', '0')) }}"
elasticsearch_data_hosts: |-
  {% set nodes = elasticsearch_data_node_details %}
  {% set data_hosts = nodes | shuffle(seed=inventory_hostname) %}
  {% if inventory_hostname in data_nodes %}
  {%   set _ = nodes.insert(0, '127.0.0.1:' ~ elastic_port) %}
  {% endif %}
  {{ data_hosts }}
logstash_data_hosts: |-
  {% set nodes = logstash_data_node_details %}
  {% set data_hosts = nodes | shuffle(seed=inventory_hostname) %}
  {% if inventory_hostname in data_nodes %}
  {%   set _ = nodes.insert(0, '127.0.0.1:' ~ logstash_beat_input_port) %}
  {% endif %}
  {{ data_hosts }}