Add cluster members configuration

elasticsearch/README.md

@@ -15,6 +15,8 @@ Tasks are extracted in several files, included in `tasks/main.yml` :
 ## Available variables
 
 * `elasticsearch_cluster_name`: cluster name ;
+* `elasticsearch_cluster_members:` members of a cluster (ex: ["10.0.0.1", "10.0.0.2", "10.0.0.3"]) (default: `Null`) ; 
+* `elasticsearch_minimum_master_nodes:` minimum of master nodes (the best practice is to have "number of elasticsearch_cluster_members / 2 + 1" as value) (default: `Null`) ; 
 * `elasticsearch_node_name`: node name, defaults to hostname ;
 * `elasticsearch_network_host`: which interfaces to bind to ;
 * `elasticsearch_network_publish_host`: which interface to publish for node-to-node communication (default: `Null`) ;

elasticsearch/defaults/main.yml

@@ -2,6 +2,8 @@
 elastic_stack_version: "6.x"
 
 elasticsearch_cluster_name: Null
+elasticsearch_cluster_members: Null
+elasticsearch_minimum_master_nodes: Null
 elasticsearch_node_name: "${HOSTNAME}"
 elasticsearch_network_host: "[_site_, _local_]"
 elasticsearch_network_publish_host: Null

elasticsearch/tasks/configuration.yml

@@ -73,3 +73,25 @@
     line: "-Xmx{{ elasticsearch_jvm_xmx }}"
   tags:
     - config
+
+- name: Configure cluster members
+  lineinfile:
+    dest: /etc/elasticsearch/elasticsearch.yml
+    line: "discovery.zen.ping.unicast.hosts:{{ elasticsearch_cluster_members }}"
+    regexp: "^discovery.zen.ping.unicast.hosts:"
+    insertafter: "^#discovery.zen.ping.unicast.hosts"
+  when: elasticsearch_cluster_members|default("", True)
+  tags:
+    - config
+
+- name: Configure minimum master nodes
+  lineinfile:
+    dest: /etc/elasticsearch/elasticsearch.yml
+    line: "discovery.zen.minimum_master_nodes:{{ elasticsearch_minimum_master_nodes }}"
+    regexp: "^discovery.zen.ping.unicast.hosts:"
+    insertafter: "^#discovery.zen.minimum_master_nodes"
+  when: elasticsearch_minimum_master_nodes|default("", True)
+  tags:
+    - config
+
+