diff --git a/src/test/igmp/igmpTest.py b/src/test/igmp/igmpTest.py
index 8b2cc11..7b1cda4 100644
--- a/src/test/igmp/igmpTest.py
+++ b/src/test/igmp/igmpTest.py
@@ -78,7 +78,7 @@
     PORT_RX_DEFAULT = 1
     max_packets = 100
     app = 'org.opencord.igmp'
-    olt_conf_file = os.path.join(os.path.dirname(os.path.realpath(__file__)), '../setup/olt_config.json')
+    olt_conf_file = os.getenv('OLT_CONFIG_FILE', os.path.join(os.path.dirname(os.path.realpath(__file__)), '../setup/olt_config.json'))
     ROVER_TEST_TIMEOUT = 300 #3600*86
     ROVER_TIMEOUT = (ROVER_TEST_TIMEOUT - 100)
     ROVER_JOIN_TIMEOUT = 60