change how we pass master nods to lb setup

Signed-off-by: Jakub Sokołowski <jakub@status.im>

README.md

@@ -6,8 +6,11 @@ This role configures a single [ElasticSearch](https://www.elastic.co/guide/en/el
 
 The only mandatory setting is what host to connect to:
 ```yaml
-es_lb_unicast_host: 'es-cluster.example.com'
-es_lb_unicast_port: 9300
+es_lb_master_nodes:
+  - node-01.es.example.tinc
+  - node-02.es.example.tinc
+  - node-03.es.example.tinc
+es_lb_master_port: 9300
 ```
 
 This is optional, but you can enable public access to the Load Balancer:

defaults/main.yml

@@ -1,4 +1,9 @@
 ---
+# Mandatory variables
+es_lb_master_nodes: ~
+es_lb_master_port: 9300
+es_lb_master_nodes_and_ports: '{{ es_master_nodes | map("regex_replace", "(.*)", "\1:"+es_master_port|string) | list }}'
+
 es_lb_image: 'docker.elastic.co/elasticsearch/elasticsearch-oss:6.5.1'
 es_lb_api_port: 9200
 es_lb_node_port: 9300
@@ -9,8 +14,6 @@ es_lb_docker_dir: '/docker/{{ es_lb_cont_name }}'
 es_lb_data_center: do-ams3
 es_lb_cluster_name: 'status-logs-search'
 es_lb_listen_addr: '0.0.0.0'
-es_lb_unicast_host: ~
-es_lb_unicast_port: 9200
 
 es_lb_max_map_count: 262144
 es_lb_jvm_min_heap: 2g

templates/elasticsearch.yml.j2

@@ -11,5 +11,4 @@ network.publish_host: "{{ ansible_local.tinc.vpn_ip }}"
 http.port: "{{ es_lb_api_port }}"
 transport.profiles.default.port: {{ es_lb_node_port }}
 
-# minimum_master_nodes need to be explicitly set when bound on a public IP
-discovery.zen.ping.unicast.hosts: {{ es_lb_unicast_host | mandatory }}:{{ es_lb_unicast_port }}
+discovery.zen.ping.unicast.hosts: {{ es_lb_master_nodes_and_ports | to_yaml }}