fixed problem passing OCN reference in env variable

Change-Id: I3ddf8aef5c3e3b81c565afed2533d35637066570
diff --git a/TestON/tests/SCPFcbench/SCPFcbench.py b/TestON/tests/SCPFcbench/SCPFcbench.py
index 414575c..42ebf5e 100644
--- a/TestON/tests/SCPFcbench/SCPFcbench.py
+++ b/TestON/tests/SCPFcbench/SCPFcbench.py
@@ -31,7 +31,7 @@
         BENCHIp = main.params[ 'BENCH' ][ 'ip1' ]
         BENCHUser = main.params[ 'BENCH' ][ 'user' ]
         CBENCHuser = main.params[ 'CBENCH'][ 'user' ]
-        MN1Ip = main.params[ 'MN' ][ 'ip1' ]
+        MN1Ip = os.environ[ main.params[ 'MN' ][ 'ip1' ] ]
         maxNodes = int(main.params[ 'availableNodes' ])
         skipMvn = main.params[ 'TEST' ][ 'skipCleanInstall' ]
         cellName = main.params[ 'ENV' ][ 'cellName' ]