diff --git a/CHANGELOG.md b/CHANGELOG.md
index da1e5aa6..00d18088 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -31,6 +31,7 @@ The **patch** part changes incrementally at each release.
 
 * certbot: install certbot dependencies non-interactively for jessie
 * elasticsearch: set tmpdir before datadir
+* elasticsearch: configure cluster with seed hosts and initial masters
 * evoacme: upstream release 20.06.1
 * evoacme: read values from environment before defaults file
 * haproxy: deport SSL tuning to Mozilla SSL generator
diff --git a/elasticsearch/defaults/main.yml b/elasticsearch/defaults/main.yml
index 91e81915..eb254807 100644
--- a/elasticsearch/defaults/main.yml
+++ b/elasticsearch/defaults/main.yml
@@ -5,9 +5,12 @@ elasticsearch_cluster_name: Null
 elasticsearch_cluster_members: Null
 elasticsearch_minimum_master_nodes: Null
 elasticsearch_node_name: "${HOSTNAME}"
-elasticsearch_network_host: "[_local_]"
+elasticsearch_network_host:
+  - "_local_"
 elasticsearch_network_publish_host: Null
 elasticsearch_http_publish_host: Null
+elasticsearch_discovery_seed_hosts: Null
+elasticsearch_cluster_initial_master_nodes: Null
 elasticsearch_custom_datadir: Null
 elasticsearch_custom_tmpdir: Null
 elasticsearch_default_tmpdir: /var/lib/elasticsearch/tmp
diff --git a/elasticsearch/tasks/configuration.yml b/elasticsearch/tasks/configuration.yml
index 50e8c98c..d4130bae 100644
--- a/elasticsearch/tasks/configuration.yml
+++ b/elasticsearch/tasks/configuration.yml
@@ -22,7 +22,7 @@
 - name: Configure network host
   lineinfile:
     dest: /etc/elasticsearch/elasticsearch.yml
-    line: "network.host: {{ elasticsearch_network_host }}"
+    line: "network.host: {{ elasticsearch_network_host | to_yaml  }}"
     regexp: "^network.host:"
     insertafter: "^# *network.host:"
   when: elasticsearch_network_host|default("", True)
@@ -32,7 +32,7 @@
 - name: Configure network publish_host
   lineinfile:
     dest: /etc/elasticsearch/elasticsearch.yml
-    line: "network.publish_host: {{ elasticsearch_network_publish_host }}"
+    line: "network.publish_host: {{ elasticsearch_network_publish_host | to_yaml  }}"
     regexp: "^network.publish_host:"
     insertafter: "^network.host:"
   when: elasticsearch_network_publish_host|default("", True)
@@ -42,13 +42,31 @@
 - name: Configure http publish_host
   lineinfile:
     dest: /etc/elasticsearch/elasticsearch.yml
-    line: "http.publish_host: {{ elasticsearch_http_publish_host }}"
+    line: "http.publish_host: {{ elasticsearch_http_publish_host | to_yaml  }}"
     regexp: "^http.publish_host:"
     insertafter: "^http.port:"
   when: elasticsearch_http_publish_host|default("", True)
   tags:
     - config
 
+- name: Configure discovery seed hosts
+  lineinfile:
+    dest: /etc/elasticsearch/elasticsearch.yml
+    line: "discovery.seed_hosts: {{ elasticsearch_discovery_seed_hosts | to_yaml }}"
+    regexp: "^discovery.seed_hosts:"
+  when: elasticsearch_discovery_seed_hosts
+  tags:
+    - config
+
+- name: Configure initial master nodes
+  lineinfile:
+    dest: /etc/elasticsearch/elasticsearch.yml
+    line: "cluster.initial_master_nodes: {{ elasticsearch_cluster_initial_master_nodes | to_yaml }}"
+    regexp: "^cluster.initial_master_nodes:"
+  when: elasticsearch_cluster_initial_master_nodes
+  tags:
+    - config
+
 - name: Configure RESTART_ON_UPGRADE
   lineinfile:
     dest: /etc/default/elasticsearch
@@ -93,5 +111,3 @@
   when: elasticsearch_minimum_master_nodes|default("", True)
   tags:
     - config
-
-