diff --git a/ironic_python_agent/hardware_managers/cna.py b/ironic_python_agent/hardware_managers/cna.py
index e29623279..6998422ae 100644
--- a/ironic_python_agent/hardware_managers/cna.py
+++ b/ironic_python_agent/hardware_managers/cna.py
@@ -14,6 +14,7 @@
 
 import os
 
+from oslo_concurrency import processutils
 from oslo_config import cfg
 from oslo_log import log
 
@@ -27,13 +28,18 @@ CONF = cfg.CONF
 def _detect_cna_card():
     addr_path = '/sys/class/net'
     for net_dev in os.listdir(addr_path):
+        link_path = '{}/{}/device/driver/module'.format(addr_path, net_dev)
         try:
-            link_command = 'readlink {}/{}/device/driver/module'.format(
-                addr_path, net_dev)
-            out = utils.execute(link_command.split())
-            if not out or out[1]:
-                continue
-        except OSError:
+            out = utils.execute('readlink', '-v', link_path)
+        except OSError as e:
+            LOG.warning('Something went wrong when readlink for '
+                        'interface %(device)s. Error: %(error)s',
+                        {'device': net_dev, 'error': e})
+            continue
+        except processutils.ProcessExecutionError as e:
+            LOG.debug('Get driver for interface %(device)s failed. '
+                      'Error: %(error)s',
+                      {'device': net_dev, 'error': e})
             continue
         driver_name = os.path.basename(out[0].strip())
         if driver_name == 'i40e':
diff --git a/ironic_python_agent/tests/unit/hardware_managers/test_cna.py b/ironic_python_agent/tests/unit/hardware_managers/test_cna.py
index 3b9226f3a..5948bb75b 100644
--- a/ironic_python_agent/tests/unit/hardware_managers/test_cna.py
+++ b/ironic_python_agent/tests/unit/hardware_managers/test_cna.py
@@ -15,6 +15,7 @@
 import os
 
 import mock
+from oslo_concurrency import processutils
 from oslo_config import cfg
 
 from ironic_python_agent import hardware
@@ -38,9 +39,9 @@ class TestIntelCnaHardwareManager(base.IronicAgentTest):
     @mock.patch.object(utils, 'execute', autospec=True)
     def test_detect_cna_card(self, mock_execute, mock_listdir):
         def mock_return_execute(*args, **kwargs):
-            if 'eth0' in args[0][1]:
+            if 'eth0' in args[2]:
                 return '/foo/bar/fake', ''
-            if 'eth1' in args[0][1]:
+            if 'eth1' in args[2]:
                 return '/foo/bar/i40e', ''
 
         mock_listdir.return_value = ['eth0', 'eth1']
@@ -51,11 +52,11 @@ class TestIntelCnaHardwareManager(base.IronicAgentTest):
     @mock.patch.object(utils, 'execute', autospec=True)
     def test_detect_cna_card_execute_error(self, mock_execute, mock_listdir):
         def mock_return_execute(*args, **kwargs):
-            if 'eth0' in args[0][1]:
+            if 'eth0' in args[2]:
                 return '/foo/bar/fake', ''
-            if 'eth1' in args[0][1]:
-                return '', 'fake error'
-            if 'eth2' in args[0][1]:
+            if 'eth1' in args[2]:
+                raise processutils.ProcessExecutionError('fake')
+            if 'eth2' in args[2]:
                 raise OSError('fake')
 
         mock_listdir.return_value = ['eth0', 'eth1', 'eth2']
@@ -66,9 +67,9 @@ class TestIntelCnaHardwareManager(base.IronicAgentTest):
     @mock.patch.object(utils, 'execute', autospec=True)
     def test_detect_cna_card_no_i40e_driver(self, mock_execute, mock_listdir):
         def mock_return_execute(*args, **kwargs):
-            if 'eth0' in args[0][1]:
+            if 'eth0' in args[2]:
                 return '/foo/bar/fake1', ''
-            if 'eth1' in args[0][1]:
+            if 'eth1' in args[2]:
                 return '/foo/bar/fake2', ''
 
         mock_listdir.return_value = ['eth0', 'eth1']