diff --git a/data/refdata/exchanges.cfg b/data/refdata/exchanges.cfg
index 188b3c4..dbb9b7c 100644
--- a/data/refdata/exchanges.cfg
+++ b/data/refdata/exchanges.cfg
@@ -14,6 +14,7 @@
         # SIM_ORDER_ENTRY_WS_PORT=28081
         # SIM_ORDER_ENTRY_REST_PORT=28082
         # SIM_ACCOUNTING_REST_PORT=28083
+        # SIM_HOST=localhost
 
         "mktdata" : {
             #