diff --git a/docs/ghostream.example.yml b/docs/ghostream.example.yml
index 4856b96..f583472 100644
--- a/docs/ghostream.example.yml
+++ b/docs/ghostream.example.yml
@@ -119,9 +119,10 @@ web:
   # e.g., on http://stream.example.com:8080/, if the domain stream.example.com is mapped to "example",
   # the stream served will be "example".
   # This implies that your domain will be able to serve only one stream.
+  # Dots in the domain name must be remplaced by underscores to avoid yaml issues.
   #
   #mapDomainToStream:
-  #  stream.example.com: example
+  #  stream_example_com: example
 
   # Stream player poster
   # Shown when stream is loading or inactive.
diff --git a/web/handler.go b/web/handler.go
index 9549032..cf3a04d 100644
--- a/web/handler.go
+++ b/web/handler.go
@@ -32,6 +32,7 @@ func viewerPostHandler(w http.ResponseWriter, r *http.Request) {
 			return
 		}
 		host = realHost
+		host = strings.Replace(host, ".", "_", -1)
 	}
 	if streamID, ok := cfg.MapDomainToStream[host]; ok {
 		path = streamID
@@ -81,6 +82,7 @@ func viewerGetHandler(w http.ResponseWriter, r *http.Request) {
 			return
 		}
 		host = realHost
+		host = strings.Replace(host, ".", "_", -1)
 	}
 	if streamID, ok := cfg.MapDomainToStream[host]; ok {
 		if path == "about" {