diff --git a/tobiko/openstack/glance/_image.py b/tobiko/openstack/glance/_image.py
index 6e12fa949..896bca414 100644
--- a/tobiko/openstack/glance/_image.py
+++ b/tobiko/openstack/glance/_image.py
@@ -18,7 +18,7 @@ import io
 import os
 import tempfile
 import time
-import typing
+import typing  # noqa
 
 from oslo_log import log
 import requests
@@ -27,6 +27,7 @@ import tobiko
 from tobiko.config import get_bool_env
 from tobiko.openstack.glance import _client
 from tobiko.openstack.glance import _io
+from tobiko.openstack import keystone
 
 
 LOG = log.getLogger(__name__)
@@ -79,15 +80,19 @@ class GlanceImageStatus(object):
     IMPORTING = u'importing'
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class GlanceImageFixture(_client.HasGlanceClientMixin, tobiko.SharedFixture):
 
-    image_name = None  # type: str
-    username = None  # type: str
-    password = None  # type: str
+    image_name: typing.Optional[str] = None
+    username: typing.Optional[str] = None
+    password: typing.Optional[str] = None
     image = None
     wait_interval = 5.
 
-    def __init__(self, image_name=None, username=None, password=None):
+    def __init__(self,
+                 image_name: typing.Optional[str] = None,
+                 username: typing.Optional[str] = None, password:
+                 typing.Optional[str] = None):
         super(GlanceImageFixture, self).__init__()
 
         if image_name:
@@ -333,7 +338,7 @@ class FileGlanceImageFixture(UploadGranceImageFixture):
 
 class URLGlanceImageFixture(FileGlanceImageFixture):
 
-    image_url = None  # type: str
+    image_url: typing.Optional[str] = None
 
     def __init__(self, image_url=None, **kwargs):
         super(URLGlanceImageFixture, self).__init__(**kwargs)
diff --git a/tobiko/openstack/heat/_stack.py b/tobiko/openstack/heat/_stack.py
index 2e6dc7c64..4d611585e 100644
--- a/tobiko/openstack/heat/_stack.py
+++ b/tobiko/openstack/heat/_stack.py
@@ -25,6 +25,7 @@ import tobiko
 from tobiko import config
 from tobiko.openstack.heat import _client
 from tobiko.openstack.heat import _template
+from tobiko.openstack import keystone
 
 
 LOG = log.getLogger(__name__)
@@ -58,6 +59,7 @@ def heat_stack_parameters(obj, stack=None):
     return parameters
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class HeatStackFixture(tobiko.SharedFixture):
     """Manages Heat stacks."""
 
diff --git a/tobiko/openstack/neutron/_extension.py b/tobiko/openstack/neutron/_extension.py
index 433593177..f17779831 100644
--- a/tobiko/openstack/neutron/_extension.py
+++ b/tobiko/openstack/neutron/_extension.py
@@ -16,9 +16,11 @@ from __future__ import absolute_import
 import collections
 
 import tobiko
+from tobiko.openstack import keystone
 from tobiko.openstack.neutron import _client
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class NetworkingExtensionsFixture(tobiko.SharedFixture):
 
     client = None
diff --git a/tobiko/shell/ping/_interface.py b/tobiko/shell/ping/_interface.py
index 7c09f21f5..029c32769 100644
--- a/tobiko/shell/ping/_interface.py
+++ b/tobiko/shell/ping/_interface.py
@@ -72,7 +72,9 @@ class PingInterfaceManager(tobiko.SharedFixture):
         usage = get_ping_usage(ssh_client)
         interface = find_ping_interface(usage=usage,
                                         interfaces=self.interfaces)
-        interface = interface or self.default_interface
+        if not interface:
+            LOG.error('Ping interface not found: using the default one')
+            interface = self.default_interface
         LOG.debug('Assign Ping interface %r to SSH client %r',
                   interface, ssh_client)
         self.client_interfaces[ssh_client] = interface
@@ -349,3 +351,38 @@ class InetToolsPingInterface(PingInterface):
         else:
             return ['-w', parameters.deadline,
                     '-W', parameters.deadline]
+
+
+IPUTILS_PING_USAGE = """
+ping: invalid option -- '-'
+Usage: ping [-aAbBdDfhLnOqrRUvV] [-c count] [-i interval] [-I interface]
+            [-m mark] [-M pmtudisc_option] [-l preload] [-p pattern] [-Q tos]
+            [-s packetsize] [-S sndbuf] [-t ttl] [-T timestamp_option]
+            [-w deadline] [-W timeout] [hop1 ...] destination
+""".strip()
+
+
+@ping_interface
+class BsdPingInterface(PingInterface):
+
+    def match_ping_usage(self, usage):
+        return usage.startswith(BSD_PING_USAGE)
+
+    has_fragment_option = False
+
+    def get_deadline_option(self, parameters):
+        return ['-t', parameters.deadline]
+
+
+BSD_PING_USAGE = """
+ping: unrecognized option `--help'
+usage: ping [-AaDdfnoQqRrv] [-c count] [-G sweepmaxsize]
+            [-g sweepminsize] [-h sweepincrsize] [-i wait]
+            [-l preload] [-M mask | time] [-m ttl] [-p pattern]
+            [-S src_addr] [-s packetsize] [-t timeout][-W waittime]
+            [-z tos] host
+       ping [-AaDdfLnoQqRrv] [-c count] [-I iface] [-i wait]
+            [-l preload] [-M mask | time] [-m ttl] [-p pattern] [-S src_addr]
+            [-s packetsize] [-T ttl] [-t timeout] [-W waittime]
+            [-z tos] mcast-group
+""".strip()
diff --git a/tobiko/shell/ping/_ping.py b/tobiko/shell/ping/_ping.py
index d0cbfcc3d..76d9d71cf 100644
--- a/tobiko/shell/ping/_ping.py
+++ b/tobiko/shell/ping/_ping.py
@@ -292,35 +292,51 @@ def handle_ping_command_error(error):
             prefix = 'ping: '
             if error.startswith('ping: '):
                 text = error[len(prefix):]
-
-                prefix = 'bad address '
-                if text.startswith(prefix):
-                    address = text[len(prefix):].replace("'", '').strip()
-                    raise _exception.BadAddressPingError(address=address)
-
-                prefix = 'local error: '
-                if text.startswith(prefix):
-                    details = text[len(prefix):].strip()
-                    raise _exception.LocalPingError(details=details)
-
-                prefix = 'sendto: '
-                if text.startswith(prefix):
-                    details = text[len(prefix):].strip()
-                    raise _exception.SendToPingError(details=details)
-
-                prefix = 'unknown host'
-                if text.startswith(prefix):
-                    details = text[len(prefix):].strip()
-                    raise _exception.UnknowHostError(details=details)
-
-                suffix = ': Name or service not known'
-                if text.endswith(suffix):
-                    details = text[:-len(suffix)].strip()
-                    raise _exception.UnknowHostError(details=details)
-
-                suffix = ': No route to host'
-                if text.endswith(suffix):
-                    details = text[:-len(suffix)].strip()
-                    raise _exception.UnknowHostError(details=details)
-
+                handle_ping_bad_address_error(text)
+                handle_ping_local_error(text)
+                handle_ping_send_to_error(text)
+                handle_ping_unknow_host_error(text)
                 raise _exception.PingError(details=text)
+
+
+def handle_ping_bad_address_error(text):
+    prefix = 'bad address '
+    if text.startswith(prefix):
+        address = text[len(prefix):].replace("'", '').strip()
+        raise _exception.BadAddressPingError(address=address)
+
+
+def handle_ping_local_error(text):
+    prefix = 'local error: '
+    if text.startswith(prefix):
+        details = text[len(prefix):].strip()
+        raise _exception.LocalPingError(details=details)
+
+
+def handle_ping_send_to_error(text):
+    prefix = 'sendto: '
+    if text.startswith(prefix):
+        details = text[len(prefix):].strip()
+        raise _exception.SendToPingError(details=details)
+
+
+def handle_ping_unknow_host_error(text):
+    prefix = 'unknown host'
+    if text.startswith(prefix):
+        details = text[len(prefix):].strip()
+        raise _exception.UnknowHostError(details=details)
+
+    suffix = ': Name or service not known'
+    if text.endswith(suffix):
+        details = text[:-len(suffix)].strip()
+        raise _exception.UnknowHostError(details=details)
+
+    suffix = ': No route to host'
+    if text.endswith(suffix):
+        details = text[:-len(suffix)].strip()
+        raise _exception.UnknowHostError(details=details)
+
+    suffix = ': Unknown host'
+    if text.endswith(suffix):
+        details = text[:-len(suffix)].strip().split()[-1]
+        raise _exception.UnknowHostError(details=details)
diff --git a/tobiko/tests/functional/docker/test_client.py b/tobiko/tests/functional/docker/test_client.py
index 2d334231e..168078f3b 100644
--- a/tobiko/tests/functional/docker/test_client.py
+++ b/tobiko/tests/functional/docker/test_client.py
@@ -21,6 +21,7 @@ import testtools
 
 import tobiko
 from tobiko import docker
+from tobiko.openstack import keystone
 from tobiko.openstack import topology
 
 
@@ -41,6 +42,7 @@ class DockerNodeFixture(tobiko.SharedFixture):
                         ' '.join(node.name for node in nodes))
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class DockerClientTest(testtools.TestCase):
 
     node = tobiko.required_setup_fixture(DockerNodeFixture)
diff --git a/tobiko/tests/functional/openstack/stacks/test_centos.py b/tobiko/tests/functional/openstack/stacks/test_centos.py
index be44acfbd..f6bbf95cd 100644
--- a/tobiko/tests/functional/openstack/stacks/test_centos.py
+++ b/tobiko/tests/functional/openstack/stacks/test_centos.py
@@ -20,11 +20,13 @@ import yaml
 
 import tobiko
 from tobiko.shell import sh
+from tobiko.openstack import keystone
 from tobiko.openstack import nova
 from tobiko.openstack import stacks
 from tobiko.tests.functional.openstack.stacks import test_cirros
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class CentosServerStackTest(test_cirros.CirrosServerStackTest):
     """Tests connectivity to Nova instances via floating IPs"""
 
diff --git a/tobiko/tests/functional/openstack/stacks/test_cirros.py b/tobiko/tests/functional/openstack/stacks/test_cirros.py
index c7f679cb7..01093ed24 100644
--- a/tobiko/tests/functional/openstack/stacks/test_cirros.py
+++ b/tobiko/tests/functional/openstack/stacks/test_cirros.py
@@ -18,11 +18,13 @@ from __future__ import absolute_import
 import testtools
 
 import tobiko
+from tobiko.openstack import keystone
 from tobiko.openstack import stacks
 from tobiko.shell import ping
 from tobiko.shell import sh
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class CirrosServerStackTest(testtools.TestCase):
     """Tests connectivity to Nova instances via floating IPs"""
 
diff --git a/tobiko/tests/functional/openstack/stacks/test_neutron.py b/tobiko/tests/functional/openstack/stacks/test_neutron.py
index 56408aab0..f5875c4e3 100644
--- a/tobiko/tests/functional/openstack/stacks/test_neutron.py
+++ b/tobiko/tests/functional/openstack/stacks/test_neutron.py
@@ -18,11 +18,13 @@ from __future__ import absolute_import
 import testtools
 
 import tobiko
+from tobiko.openstack import keystone
 from tobiko.openstack import neutron
 from tobiko.openstack import stacks
 
 
-class NetworkTestCase(testtools.TestCase):
+@keystone.skip_unless_has_keystone_credentials()
+class NetworkTest(testtools.TestCase):
     """Tests network creation"""
 
     #: Stack of resources with a network with a gateway router
@@ -78,8 +80,9 @@ class NetworkTestCase(testtools.TestCase):
             self.stack.ipv6_gateway_addresses)
 
 
+@keystone.skip_unless_has_keystone_credentials()
 @neutron.skip_if_missing_networking_extensions('net-mtu-write')
-class NetworkWithNetMtuWriteTestCase(NetworkTestCase):
+class NetworkWithNetMtuWriteTest(NetworkTest):
 
     #: Stack of resources with a network with a gateway router
     stack = tobiko.required_setup_fixture(
@@ -89,15 +92,17 @@ class NetworkWithNetMtuWriteTestCase(NetworkTestCase):
         self.assertEqual(self.stack.mtu, self.stack.outputs.mtu)
 
 
+@keystone.skip_unless_has_keystone_credentials()
 @neutron.skip_if_missing_networking_extensions('l3-ha')
 @neutron.skip_if_missing_networking_agents(binary='neutron-l3-agent',
                                            count=2)
-class L3HaNetworkTestCase(NetworkTestCase):
+class L3HaNetworkTest(NetworkTest):
 
     #: Stack of resources with a network with a gateway router
     stack = tobiko.required_setup_fixture(stacks.L3haNetworkStackFixture)
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class FloatingNetworkStackTest(testtools.TestCase):
 
     @stacks.skip_if_missing_floating_network
diff --git a/tobiko/tests/functional/openstack/test_keystone.py b/tobiko/tests/functional/openstack/test_keystone.py
index d60b4531f..24b20ba18 100644
--- a/tobiko/tests/functional/openstack/test_keystone.py
+++ b/tobiko/tests/functional/openstack/test_keystone.py
@@ -31,6 +31,7 @@ LOG = log.getLogger(__name__)
 CIENT_CLASSSES = v2_client.Client, v3_client.Client
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class TobikoKeystoneCredentialsCommandTest(testtools.TestCase):
 
     def test_execute(self):
@@ -41,6 +42,7 @@ class TobikoKeystoneCredentialsCommandTest(testtools.TestCase):
         self.assertEqual(expected, actual)
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class KeystoneClientAPITest(testtools.TestCase):
 
     def test_get_keystone_client(self):
diff --git a/tobiko/tests/functional/openstack/test_neutron.py b/tobiko/tests/functional/openstack/test_neutron.py
index 8b3f9fe42..bb757fe55 100644
--- a/tobiko/tests/functional/openstack/test_neutron.py
+++ b/tobiko/tests/functional/openstack/test_neutron.py
@@ -20,6 +20,7 @@ import testtools
 
 import tobiko
 from tobiko import config
+from tobiko.openstack import keystone
 from tobiko.openstack import neutron
 from tobiko.openstack import nova
 from tobiko.openstack import stacks
@@ -29,6 +30,7 @@ from tobiko.openstack import tests
 CONF = config.CONF
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class NeutronApiTestCase(testtools.TestCase):
     """Tests network creation"""
 
@@ -112,6 +114,7 @@ class NeutronApiTestCase(testtools.TestCase):
         self.assertIn(agent['id'], {a['id'] for a in agents})
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class PortTest(testtools.TestCase):
 
     #: Stack of resources with a network with a gateway router
@@ -159,6 +162,7 @@ class PortTest(testtools.TestCase):
             self.assertIn(port_address, cidr)
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class AgentTest(testtools.TestCase):
 
     def test_skip_if_missing_agents(self, count=1, should_skip=False,
@@ -192,9 +196,6 @@ class AgentTest(testtools.TestCase):
         self.test_skip_if_missing_agents(count=1000000,
                                          should_skip=True)
 
-
-class NeutronAgentTest(testtools.TestCase):
-
     def test_neutron_agents_are_alive(self):
         agents = tests.test_neutron_agents_are_alive()
         # check has agents and they are all alive
diff --git a/tobiko/tests/functional/openstack/test_nova.py b/tobiko/tests/functional/openstack/test_nova.py
index f71109cde..9dfb0b0fa 100644
--- a/tobiko/tests/functional/openstack/test_nova.py
+++ b/tobiko/tests/functional/openstack/test_nova.py
@@ -21,6 +21,7 @@ import netaddr
 import testtools
 
 import tobiko
+from tobiko.openstack import keystone
 from tobiko.openstack import nova
 from tobiko.openstack import stacks
 
@@ -34,6 +35,7 @@ class KeyPairTest(testtools.TestCase):
         self.assertTrue(os.path.isfile(self.stack.key_file + '.pub'))
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class ClientTest(testtools.TestCase):
 
     #: Stack of resources with a server attached to a floating IP
@@ -117,6 +119,7 @@ class ClientTest(testtools.TestCase):
         self.assertEqual('ACTIVE', server.status)
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class HypervisorTest(testtools.TestCase):
 
     def test_skip_if_missing_hypervisors(self, count=1, should_skip=False,
@@ -152,6 +155,7 @@ class HypervisorTest(testtools.TestCase):
                                               should_skip=True)
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class ServiceTest(testtools.TestCase):
 
     def test_wait_for_services_up(self):
diff --git a/tobiko/tests/functional/openstack/test_octavia.py b/tobiko/tests/functional/openstack/test_octavia.py
index 4aad8ad78..be0b5f58c 100644
--- a/tobiko/tests/functional/openstack/test_octavia.py
+++ b/tobiko/tests/functional/openstack/test_octavia.py
@@ -21,6 +21,7 @@ from tobiko.openstack import keystone
 from tobiko.openstack import octavia
 
 
+@keystone.skip_unless_has_keystone_credentials()
 @keystone.skip_if_missing_service(name='octavia')
 class OctaviaClientAPITest(testtools.TestCase):
 
diff --git a/tobiko/tests/functional/openstack/test_topology.py b/tobiko/tests/functional/openstack/test_topology.py
index caa772c29..93407156c 100644
--- a/tobiko/tests/functional/openstack/test_topology.py
+++ b/tobiko/tests/functional/openstack/test_topology.py
@@ -18,12 +18,14 @@ from __future__ import absolute_import
 import testtools
 
 import tobiko
+from tobiko.openstack import keystone
 from tobiko.openstack import nova
 from tobiko.openstack import topology
 from tobiko.shell import ping
 from tobiko.shell import sh
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class OpenStackTopologyTest(testtools.TestCase):
 
     topology = tobiko.required_setup_fixture(topology.OpenStackTopology)
diff --git a/tobiko/tests/functional/openstack/tests/test_nova.py b/tobiko/tests/functional/openstack/tests/test_nova.py
index 0d79dac93..ef7339380 100644
--- a/tobiko/tests/functional/openstack/tests/test_nova.py
+++ b/tobiko/tests/functional/openstack/tests/test_nova.py
@@ -19,6 +19,7 @@ import testtools
 
 import tobiko
 from tobiko.openstack import glance
+from tobiko.openstack import keystone
 from tobiko.openstack import nova
 from tobiko.openstack import tests
 
@@ -27,6 +28,7 @@ class MyServerStack(tests.TestServerCreationStack):
     pass
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class ServerCreationTest(testtools.TestCase):
 
     def test_server_creation(self):
diff --git a/tobiko/tests/functional/podman/test_client.py b/tobiko/tests/functional/podman/test_client.py
index 01df125d0..38dab57cf 100644
--- a/tobiko/tests/functional/podman/test_client.py
+++ b/tobiko/tests/functional/podman/test_client.py
@@ -21,6 +21,7 @@ import testtools
 
 import tobiko
 from tobiko import podman
+from tobiko.openstack import keystone
 from tobiko.openstack import topology
 
 
@@ -41,6 +42,7 @@ class PodmanNodeFixture(tobiko.SharedFixture):
                         ' '.join(node.name for node in nodes))
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class PodmanClientTest(testtools.TestCase):
 
     node = tobiko.required_setup_fixture(PodmanNodeFixture)
diff --git a/tobiko/tests/functional/shell/fixtures.py b/tobiko/tests/functional/shell/fixtures.py
index 7003158d2..957cf6d39 100644
--- a/tobiko/tests/functional/shell/fixtures.py
+++ b/tobiko/tests/functional/shell/fixtures.py
@@ -1,10 +1,12 @@
 from __future__ import absolute_import
 
 import tobiko
+from tobiko.openstack import keystone
 from tobiko.openstack import topology
 from tobiko.shell import ip
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class NetworkNamespaceFixture(tobiko.SharedFixture):
 
     network_namespace = None
diff --git a/tobiko/tests/functional/shell/test_hostname.py b/tobiko/tests/functional/shell/test_hostname.py
index 4fe4d4e07..8fa38d9db 100644
--- a/tobiko/tests/functional/shell/test_hostname.py
+++ b/tobiko/tests/functional/shell/test_hostname.py
@@ -23,9 +23,11 @@ import testtools
 import tobiko
 from tobiko.shell import sh
 from tobiko.shell import ssh
+from tobiko.openstack import keystone
 from tobiko.openstack import stacks
 
 
+@keystone.skip_unless_has_keystone_credentials()
 class HostnameTest(testtools.TestCase):
 
     server_stack = tobiko.required_setup_fixture(
diff --git a/tobiko/tests/functional/shell/test_ifconfig.py b/tobiko/tests/functional/shell/test_ifconfig.py
index 819531b08..dce8f38c8 100644
--- a/tobiko/tests/functional/shell/test_ifconfig.py
+++ b/tobiko/tests/functional/shell/test_ifconfig.py
@@ -22,6 +22,7 @@ import tobiko
 from tobiko.shell import ifconfig
 from tobiko.shell import sh
 from tobiko.shell import ssh
+from tobiko.openstack import keystone
 from tobiko.openstack import stacks
 
 
@@ -53,9 +54,11 @@ class IfconfigTest(testtools.TestCase):
     def test_list_ip_addresses_with_ipv6(self):
         self.test_list_ip_addresses(ip_version=6)
 
+    @keystone.skip_unless_has_keystone_credentials()
     def test_list_ip_addresses_with_cirros_server(self):
         self.test_list_ip_addresses(ssh_client=self.cirros_stack.ssh_client)
 
+    @keystone.skip_unless_has_keystone_credentials()
     def test_list_ip_addresses_with_ubuntu_server(self):
         self.test_list_ip_addresses(ssh_client=self.ubuntu_stack.ssh_client)
 
diff --git a/tobiko/tests/functional/shell/test_ip.py b/tobiko/tests/functional/shell/test_ip.py
index 0e960fe00..6ecb64412 100644
--- a/tobiko/tests/functional/shell/test_ip.py
+++ b/tobiko/tests/functional/shell/test_ip.py
@@ -15,8 +15,9 @@
 #    under the License.
 from __future__ import absolute_import
 
+import os
+
 import netaddr
-import six
 import testtools
 
 import tobiko
@@ -41,6 +42,8 @@ class IpTest(testtools.TestCase):
 
     def test_list_ip_addresses(self, ip_version=None, scope=None,
                                **execute_params):
+        if not os.path.isfile('/bin/ip'):
+            self.skip("'bin/ip' command not found")
         ips = ip.list_ip_addresses(ip_version=ip_version, scope=scope,
                                    **execute_params)
         self.assertIsInstance(ips, tobiko.Selection)
@@ -125,10 +128,12 @@ class IpTest(testtools.TestCase):
                                     **execute_params)
 
     def test_list_namespaces(self, **execute_params):
+        if not os.path.isfile('/bin/ip'):
+            self.skip("'bin/ip' command not found")
         namespaces = ip.list_network_namespaces(**execute_params)
         self.assertIsInstance(namespaces, list)
         for namespace in namespaces:
-            self.assertIsInstance(namespace, six.string_types)
+            self.assertIsInstance(namespace, str)
             self.test_list_ip_addresses(network_namespace=namespace)
 
     def test_list_namespaces_with_centos_server(self):
diff --git a/tobiko/tests/functional/shell/test_ping.py b/tobiko/tests/functional/shell/test_ping.py
index e9a2855d0..ecac7e7ac 100644
--- a/tobiko/tests/functional/shell/test_ping.py
+++ b/tobiko/tests/functional/shell/test_ping.py
@@ -15,6 +15,8 @@
 #    under the License.
 from __future__ import absolute_import
 
+import os
+
 import netaddr
 import testtools
 
@@ -98,6 +100,8 @@ class PingTest(testtools.TestCase):
 
     def test_ping_hosts(self, ssh_client=None, network_namespace=None,
                         **params):
+        if not os.path.isfile('/sbin/ip'):
+            self.skip("'/sbin/ip' command not found")
         ips = ip.list_ip_addresses(ssh_client=ssh_client,
                                    network_namespace=network_namespace)
         reachable_ips, unrecheable_ips = ping.ping_hosts(
diff --git a/tools/common.py b/tools/common.py
index 3bf3de638..f87f73488 100644
--- a/tools/common.py
+++ b/tools/common.py
@@ -51,18 +51,20 @@ def normalize_path(path):
 def execute(command, *args, **kwargs):
     capture_stdout = kwargs.pop('capture_stdout', True)
     universal_newlines = kwargs.pop('universal_newlines', True)
+    check = kwargs.pop('check', True)
 
     if args or kwargs:
         command = command.format(*args, **kwargs)
     command = command.strip()
 
-    if capture_stdout:
-        execute_func = subprocess.check_output
-    else:
-        execute_func = subprocess.check_call
+    stdout = capture_stdout and subprocess.PIPE or None
 
-    return execute_func(['/bin/bash', '-x', '-c', command],
-                        shell=False, universal_newlines=universal_newlines)
+    result = subprocess.run(['/bin/bash', '-x', '-c', command],
+                            stdout=stdout, shell=False,
+                            universal_newlines=universal_newlines)
+    if check:
+        result.check_returncode()
+    return result.stdout
 
 
 def get_posargs(args=None):
diff --git a/tools/run_tests.py b/tools/run_tests.py
index 3eca5f903..67f57002b 100755
--- a/tools/run_tests.py
+++ b/tools/run_tests.py
@@ -106,7 +106,8 @@ def log_environ():
 def log_tests_results():
     common.execute('stestr last --all-attachments >> "{log_file}"',
                    log_file=TOX_REPORT_LOG,
-                   capture_stdout=False)
+                   capture_stdout=False,
+                   check=False)
 
 
 def run_test_cases():
diff --git a/tox.ini b/tox.ini
index 25e63c52c..fa1cf35ea 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,6 +1,6 @@
 [tox]
 
-envlist = bindep,linters,py3,lower-constraints
+envlist = bindep,linters,py3,lower-constraints,functional
 minversion = 3.8.0