diff --git a/lib/quantum_plugins/bigswitch_floodlight b/lib/quantum_plugins/bigswitch_floodlight
index 35276a5..2c928be 100644
--- a/lib/quantum_plugins/bigswitch_floodlight
+++ b/lib/quantum_plugins/bigswitch_floodlight
@@ -2,7 +2,7 @@
 # ------------------------------------
 
 # Save trace setting
-XTRACE=$(set +o | grep xtrace)
+MY_XTRACE=$(set +o | grep xtrace)
 set +o xtrace
 
 source $TOP_DIR/lib/quantum_plugins/ovs_base
@@ -52,4 +52,4 @@
 }
 
 # Restore xtrace
-$XTRACE
+$MY_XTRACE
diff --git a/lib/quantum_plugins/linuxbridge b/lib/quantum_plugins/linuxbridge
index e8ba68c..6d5d4e0 100644
--- a/lib/quantum_plugins/linuxbridge
+++ b/lib/quantum_plugins/linuxbridge
@@ -2,7 +2,7 @@
 # ---------------------------
 
 # Save trace setting
-XTRACE=$(set +o | grep xtrace)
+MY_XTRACE=$(set +o | grep xtrace)
 set +o xtrace
 
 function is_quantum_ovs_base_plugin() {
@@ -76,4 +76,4 @@
 }
 
 # Restore xtrace
-$XTRACE
+$MY_XTRACE
diff --git a/lib/quantum_plugins/openvswitch b/lib/quantum_plugins/openvswitch
index 5415e86..12bc244 100644
--- a/lib/quantum_plugins/openvswitch
+++ b/lib/quantum_plugins/openvswitch
@@ -2,7 +2,7 @@
 # ---------------------------
 
 # Save trace setting
-XTRACE=$(set +o | grep xtrace)
+MY_XTRACE=$(set +o | grep xtrace)
 set +o xtrace
 
 source $TOP_DIR/lib/quantum_plugins/ovs_base
@@ -141,4 +141,4 @@
 }
 
 # Restore xtrace
-$XTRACE
+$MY_XTRACE
diff --git a/lib/quantum_plugins/ovs_base b/lib/quantum_plugins/ovs_base
index d9f6fd0..4c33473 100644
--- a/lib/quantum_plugins/ovs_base
+++ b/lib/quantum_plugins/ovs_base
@@ -2,7 +2,7 @@
 # -------------------------------------
 
 # Save trace setting
-XTRACE=$(set +o | grep xtrace)
+MY_XTRACE=$(set +o | grep xtrace)
 set +o xtrace
 
 function is_quantum_ovs_base_plugin() {
@@ -46,4 +46,4 @@
 }
 
 # Restore xtrace
-$XTRACE
+$MY_XTRACE
diff --git a/lib/quantum_plugins/ryu b/lib/quantum_plugins/ryu
index 86105bc..f44f4ae 100644
--- a/lib/quantum_plugins/ryu
+++ b/lib/quantum_plugins/ryu
@@ -2,7 +2,7 @@
 # ------------------
 
 # Save trace setting
-XTRACE=$(set +o | grep xtrace)
+MY_XTRACE=$(set +o | grep xtrace)
 set +o xtrace
 
 source $TOP_DIR/lib/quantum_plugins/ovs_base
@@ -60,4 +60,4 @@
 }
 
 # Restore xtrace
-$XTRACE
+$MY_XTRACE
diff --git a/lib/quantum_thirdparty/bigswitch_floodlight b/lib/quantum_thirdparty/bigswitch_floodlight
index 77aeb61..60e3924 100644
--- a/lib/quantum_thirdparty/bigswitch_floodlight
+++ b/lib/quantum_thirdparty/bigswitch_floodlight
@@ -2,7 +2,7 @@
 # ------------------------------------------
 
 # Save trace setting
-XTRACE=$(set +o | grep xtrace)
+MY_XTRACE=$(set +o | grep xtrace)
 set +o xtrace
 
 BS_FL_CONTROLLERS_PORT=${BS_FL_CONTROLLERS_PORT:-localhost:80}
@@ -47,4 +47,4 @@
 }
 
 # Restore xtrace
-$XTRACE
+$MY_XTRACE
diff --git a/lib/quantum_thirdparty/ryu b/lib/quantum_thirdparty/ryu
index f11951a..de8e086 100644
--- a/lib/quantum_thirdparty/ryu
+++ b/lib/quantum_thirdparty/ryu
@@ -2,7 +2,7 @@
 # -----------------------
 
 # Save trace setting
-XTRACE=$(set +o | grep xtrace)
+MY_XTRACE=$(set +o | grep xtrace)
 set +o xtrace
 
 
@@ -62,4 +62,4 @@
 }
 
 # Restore xtrace
-$XTRACE
+$MY_XTRACE