diff --git a/libraries/utils.robot b/libraries/utils.robot
index 892d457..2cfe4ea 100644
--- a/libraries/utils.robot
+++ b/libraries/utils.robot
@@ -351,7 +351,7 @@
     #Run Keyword    Wait Until Keyword Succeeds    ${timeout}    5s    Validate OLT Flows    ${olt_flows}
     #${List_ONU_Serial}    Create List
     #Set Suite Variable    ${List_ONU_Serial}
-    #Build ONU SN List    ${List_ONU_Serial}
+    #Build ONU SN List    ${List_ONU_Serial}    ${olt_serial_number}
     #Log    ${List_ONU_Serial}
     #Run Keyword    Wait Until Keyword Succeeds    ${timeout}    5s    Validate ONU Flows
     #...    ${List_ONU_Serial}    ${onu_flows}
@@ -380,7 +380,7 @@
         ...    ${olt_device_id}
         ${List_ONU_Serial}    Create List
         Set Suite Variable    ${List_ONU_Serial}
-        Build ONU SN List    ${List_ONU_Serial}
+        Build ONU SN List    ${List_ONU_Serial}    ${olt_serial_number}
         Log    ${List_ONU_Serial}
         Run Keyword    Wait Until Keyword Succeeds    ${timeout}    5s    Validate ONU Flows
         ...    ${List_ONU_Serial}    ${onu_flows}
diff --git a/libraries/voltctl.robot b/libraries/voltctl.robot
index c7819e1..59b85f9 100755
--- a/libraries/voltctl.robot
+++ b/libraries/voltctl.robot
@@ -674,10 +674,11 @@
     [Return]    ${id}
 
 Build ONU SN List
-    [Arguments]    ${serial_numbers}    ${num_onus}=${num_all_onus}
-    [Documentation]    Appends all ONU SNs to the ${serial_numbers} list
+    [Arguments]    ${serial_numbers}    ${olt_serial_number}=${EMPTY}    ${num_onus}=${num_all_onus}
+    [Documentation]    Appends all ONU SNs for the given OLT to the ${serial_numbers} list
     FOR    ${INDEX}    IN RANGE    0    ${num_onus}
-        Append To List    ${serial_numbers}    ${hosts.src[${INDEX}].onu}
+    Run Keyword IF  "${olt_serial_number}"=="${hosts.src[${INDEX}].olt}" or "${olt_serial_number}"=="${EMPTY}"
+    ...   Append To List    ${serial_numbers}    ${hosts.src[${INDEX}].onu}
     END
 
 Get SN From Device ID
diff --git a/tests/dt-workflow/Voltha_DT_FailureScenarios.robot b/tests/dt-workflow/Voltha_DT_FailureScenarios.robot
index 7ad96f3..7b91460 100644
--- a/tests/dt-workflow/Voltha_DT_FailureScenarios.robot
+++ b/tests/dt-workflow/Voltha_DT_FailureScenarios.robot
@@ -135,7 +135,7 @@
     #Run Keyword    Wait Until Keyword Succeeds    ${timeout}    5s    Validate OLT Flows    ${olt_flows}
     #${List_ONU_Serial}    Create List
     #Set Suite Variable    ${List_ONU_Serial}
-    #Build ONU SN List    ${List_ONU_Serial}
+    #Build ONU SN List    ${List_ONU_Serial}    ${olt_serial_number}
     #Log    ${List_ONU_Serial}
     #Run Keyword    Wait Until Keyword Succeeds    ${timeout}    5s    Validate ONU Flows
     #...    ${List_ONU_Serial}    ${onu_flows}
diff --git a/tests/dt-workflow/Voltha_DT_PODTests.robot b/tests/dt-workflow/Voltha_DT_PODTests.robot
index ce8409a..36ff38b 100644
--- a/tests/dt-workflow/Voltha_DT_PODTests.robot
+++ b/tests/dt-workflow/Voltha_DT_PODTests.robot
@@ -268,7 +268,7 @@
         ...    ${olt_device_id}
         ${List_ONU_Serial}    Create List
         Set Suite Variable    ${List_ONU_Serial}
-        Build ONU SN List    ${List_ONU_Serial}    ${num_onus}
+        Build ONU SN List    ${List_ONU_Serial}    ${num_onus}    ${olt_serial_number}
         Log    ${List_ONU_Serial}
         Run Keyword    Wait Until Keyword Succeeds    ${timeout}    5s    Validate ONU Flows
         ...    ${List_ONU_Serial}    ${onu_flows}