[SEBA-884] read config from file
Change-Id: I09c24f5c9504a51d804e68a99a2ac3a02d730573
diff --git a/docs/source/index.rst b/docs/source/index.rst
index 2f23dde..fff0bfd 100644
--- a/docs/source/index.rst
+++ b/docs/source/index.rst
@@ -113,3 +113,7 @@
Number of PON ports per OLT device to be emulated (default 1)
-s_tag int
S-Tag value (default 900)
+
+``BBSim`` also looks for a configuration file in ``configs/bbsim.yaml`` from which it reads a number of default settings. The command line options listed above override the corresponding coniguration file settings. A sample configuration file is given below:
+
+.. literalinclude:: ../../configs/bbsim.yaml