diff --git a/requirements.txt b/requirements.txt
index 5684f0b7..601358c1 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -11,6 +11,6 @@ click>=4.1
 prettytable>=0.7
 tzlocal
 python-dateutil
-psutil
+psutil>=2.0.0
 cdiff
 kubernetes>=2.0.0,<=7.0.0,!=4.0.*,!=5.0.*
diff --git a/tests/test_api.py b/tests/test_api.py
index 8d3ed0ca..721a3932 100644
--- a/tests/test_api.py
+++ b/tests/test_api.py
@@ -403,4 +403,7 @@ class TestRestApiServer(unittest.TestCase):
         srv.reload_config({'listen': '127.0.0.2:8008'})
 
     def test_handle_error(self):
-        self.assertIsNone(MockRestApiServer.handle_error(None, ('127.0.0.1', 55555)))
+        try:
+            raise Exception()
+        except Exception:
+            self.assertIsNone(MockRestApiServer.handle_error(None, ('127.0.0.1', 55555)))
diff --git a/tests/test_log.py b/tests/test_log.py
index bf19ad5a..5363e782 100644
--- a/tests/test_log.py
+++ b/tests/test_log.py
@@ -11,8 +11,8 @@ from patroni.log import PatroniLogger
 class TestPatroniLogger(unittest.TestCase):
 
     @patch('logging.FileHandler._open', Mock())
-    def setUp(self):
-        self.config = {
+    def test_patroni_logger(self):
+        config = {
             'log': {
                 'dir': 'foo',
                 'file_size': 4096,
@@ -24,15 +24,13 @@ class TestPatroniLogger(unittest.TestCase):
             'restapi': {}, 'postgresql': {'data_dir': 'foo'}
         }
         sys.argv = ['patroni.py']
-        os.environ[Config.PATRONI_CONFIG_VARIABLE] = yaml.dump(self.config, default_flow_style=False)
-        self.logger = PatroniLogger()
-        config = Config()
-        self.logger.reload_config(config['log'])
+        os.environ[Config.PATRONI_CONFIG_VARIABLE] = yaml.dump(config, default_flow_style=False)
+        logger = PatroniLogger()
+        patroni_config = Config()
+        logger.reload_config(patroni_config['log'])
 
-    def test_rotating_handler(self):
-        self.assertEqual(self.logger.handler.maxBytes, self.config['log']['file_size'])
-        self.assertEqual(self.logger.handler.backupCount, self.config['log']['file_num'])
+        self.assertEqual(logger.handler.maxBytes, config['log']['file_size'])
+        self.assertEqual(logger.handler.backupCount, config['log']['file_num'])
 
-    def test_reload_config(self):
-        self.config['log'].pop('dir')
-        self.logger.reload_config(self.config['log'])
+        config['log'].pop('dir')
+        logger.reload_config(config['log'])
diff --git a/tests/test_postmaster.py b/tests/test_postmaster.py
index ee951c64..c2b64032 100644
--- a/tests/test_postmaster.py
+++ b/tests/test_postmaster.py
@@ -48,7 +48,7 @@ class TestPostmasterProcess(unittest.TestCase):
         mock_init.side_effect = psutil.NoSuchProcess(123)
         self.assertEqual(PostmasterProcess.from_pid(123), None)
         mock_init.side_effect = None
-        self.assertNotEquals(PostmasterProcess.from_pid(123), None)
+        self.assertNotEqual(PostmasterProcess.from_pid(123), None)
 
     @patch('psutil.Process.__init__', Mock())
     @patch('psutil.Process.send_signal')