diff --git a/os_net_config/tests/test_utils.py b/os_net_config/tests/test_utils.py
index 35cb812d..6c45c46e 100644
--- a/os_net_config/tests/test_utils.py
+++ b/os_net_config/tests/test_utils.py
@@ -584,6 +584,44 @@ class TestUtils(base.TestCase):
     def test_interface_mac_raises(self):
         self.assertRaises(IOError, utils.interface_mac, 'ens20f2p3')
 
+    def test_get_dpdk_devargs_mlnx(self):
+        def test_execute(name, dummy1, dummy2=None, dummy3=None):
+            if 'ethtool' in name:
+                out = _PCI_OUTPUT
+                return out, None
+
+        def test_get_stored_pci_address(ifname, noop):
+            return "0000:00:07.0"
+
+        self.stub_out('oslo_concurrency.processutils.execute', test_execute)
+        self.stub_out('os_net_config.utils.get_stored_pci_address',
+                      test_get_stored_pci_address)
+        tmpdir = tempfile.mkdtemp()
+        self.stub_out('os_net_config.utils._SYS_CLASS_NET', tmpdir)
+        nic = 'p4p1'
+        nic_path = os.path.join(tmpdir, nic)
+        os.makedirs(nic_path)
+        os.makedirs(os.path.join(nic_path, 'device'))
+        # Testing standard Mellanox Connect-X cards
+        with open(os.path.join(nic_path, 'operstate'), 'w') as f:
+            f.write('up')
+        with open(os.path.join(nic_path, 'address'), 'w') as f:
+            f.write('00:0f:21:69:39:14')
+        with open(os.path.join(nic_path, 'device', 'vendor'), 'w') as f:
+            f.write('0x15b3')
+        self.assertEqual(utils.get_dpdk_devargs(nic, False),
+                         '0000:00:19.0')
+        # now testing the Mellanox CX3
+        with open(os.path.join(nic_path, 'device', 'device'), 'w') as f:
+            f.write('0x1007')
+        self.assertEqual(utils.get_dpdk_devargs(nic, False),
+                         'class=eth,mac=00:0f:21:69:39:14')
+        with open(os.path.join(nic_path, 'device', 'vendor'), 'w') as f:
+            f.write('0x15b4')
+        self.assertEqual(utils.get_dpdk_devargs(nic, False),
+                         '0000:00:07.0')
+        shutil.rmtree(tmpdir)
+
     def test_is_active_nic_for_sriov_vf(self):
 
         tmpdir = tempfile.mkdtemp()
diff --git a/os_net_config/utils.py b/os_net_config/utils.py
index 6e346c84..b02ba91d 100644
--- a/os_net_config/utils.py
+++ b/os_net_config/utils.py
@@ -105,14 +105,14 @@ def get_file_data(filename):
 
 def interface_mac(name):
     try:  # If the iface is part of a Linux bond, the real MAC is only here.
-        with open('/sys/class/net/%s/bonding_slave/perm_hwaddr' % name,
+        with open(_SYS_CLASS_NET + '/%s/bonding_slave/perm_hwaddr' % name,
                   'r') as f:
             return f.read().rstrip()
     except IOError:
         pass  # Iface is not part of a bond, continue
 
     try:
-        with open('/sys/class/net/%s/address' % name, 'r') as f:
+        with open(_SYS_CLASS_NET + '/%s/address' % name, 'r') as f:
             return f.read().rstrip()
     except IOError:
         # If the interface is bound to a DPDK driver, get the mac address from
@@ -385,13 +385,23 @@ def get_dpdk_devargs(ifname, noop):
     if not noop:
         vendor_id = get_vendor_id(ifname)
         device_id = get_device_id(ifname)
-        if vendor_id == "0x15b3" and device_id == "0x1007":
-            # Some NICs (i.e. Mellanox ConnectX-3) have only one PCI address
-            # associated with multiple ports. Using a PCI device won’t work.
-            # Instead, we should use "class=eth,mac=<MAC>"
-            dpdk_devargs = "class=eth,mac=%s" % interface_mac(ifname)
+        if vendor_id == "0x15b3":
+            logger.info("Getting devargs for Mellanox cards")
+            if device_id == "0x1007":
+                # Some NICs (i.e. Mellanox ConnectX-3) have only one PCI
+                # address associated with multiple ports. Using a PCI
+                # device won’t work. Instead, we should use
+                # "class=eth,mac=<MAC>"
+                dpdk_devargs = "class=eth,mac=%s" % interface_mac(ifname)
+            elif is_active_nic(ifname):
+                # Other Mellanox devices are active and they are not stored
+                # in dpdk_mapping.yaml file, so we need to get their pci
+                # address with ethtool.
+                dpdk_devargs = get_pci_address(ifname, noop)
         else:
+            logger.info("Getting stored PCI address as devarg")
             dpdk_devargs = get_stored_pci_address(ifname, noop)
+        logger.debug("Devargs found: %s" % (dpdk_devargs))
         return dpdk_devargs