requiring dhclient to run in background

Change-Id: Ifef010aba9035acd5ab17b229cf73d1904b26465
diff --git a/src/test/cord-api/Framework/DHCP.robot b/src/test/cord-api/Framework/DHCP.robot
index 3444041..fbf62b5 100644
--- a/src/test/cord-api/Framework/DHCP.robot
+++ b/src/test/cord-api/Framework/DHCP.robot
@@ -23,7 +23,7 @@
     [Documentation]    SSH's into the RG (src) and executes a dhclient against a particular interface
     ${conn_id}=    SSHLibrary.Open Connection    ${ip}    prompt=${prompt}    timeout=${prompt_timeout}
     SSHLibrary.Login    ${user}    ${pass}
-    SSHLibrary.Write    sudo dhclient ${iface}
+    SSHLibrary.Write    sudo dhclient -nw ${iface}
     Read Until    [sudo] password for ${user}:
     SSHLibrary.Write    ${pass}
     ${result}=    Read Until    ${prompt}