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@@ -1,3 +1,9 @@
 # Elasticsearch Cluster
 
-A scalable Elasticsearch cluster
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+A scalable Elasticsearch cluster
+
+## Notes
+
+You have to set vm.max_map_count to atleast 262144 on each of the hosts that will run Elasticsearch!
+
+To do so run `sudo sysctl -w vm.max_map_count=262144`
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