-cd ${ROOTDIR}/dpdk-16.07/
-./tools/dpdk-devbind.py -b ${port1_driver} ${port1_pci}
-./tools/dpdk-devbind.py -b ${port2_driver} ${port2_pci}
+# Unbind interfaces
+cd ${ROOTDIR}/${DPDK_VERSION}/
+sudo ./usertools/dpdk-devbind.py -b ${port1_driver} ${port1_pci} || \
+ echo "Unbind ${port1_pci} failed" || exit 1
+sudo ./usertools/dpdk-devbind.py -b ${port2_driver} ${port2_pci} || \
+ echo "Unbind ${port1_pci} failed" || exit 1