diff --git a/docs/index.asciidoc b/docs/index.asciidoc
index ddb0141d5..7b9b0f8bc 100644
--- a/docs/index.asciidoc
+++ b/docs/index.asciidoc
@@ -523,6 +523,16 @@ should reference only data or client nodes in Elasticsearch.
 Any special characters present in the URLs here MUST be URL escaped! This means
 `#` should be put in as `%23` for instance.
 
+This option can accept an environment variable containing one or more hostnames separated by whitespace.
+Strings separated by whitespace are treated as separate entries.
+
+Examples:
+
+    `ES_HOSTS="es1.example.com es2.example.com:9201 es3.example.com:9201"`
+    `ES_HOSTS="127.0.0.1:9200 127.0.0.2:9200"`
+    `ES_HOSTS="http://127.0.0.1 http://127.0.0.2"`
+    `ES_HOSTS="https://127.0.0.1:9200/mypath https://127.0.0.2:9200/mypath"`
+
 [id="plugins-{type}s-{plugin}-http_compression"]
 ===== `http_compression`