diff --git a/doc/helpers.rst b/doc/helpers.rst
index c7ea422d3..78b7e4d96 100644
--- a/doc/helpers.rst
+++ b/doc/helpers.rst
@@ -28,6 +28,11 @@ Decorators
 .. automodule:: fuelweb_test.helpers.decorators
    :members:
 
+Metaclasses
+-----------
+.. automodule:: fuelweb_test.helpers.metaclasses
+   :members:
+
 Eb tables
 ---------
 .. automodule:: fuelweb_test.helpers.eb_tables
diff --git a/fuelweb_test/__init__.py b/fuelweb_test/__init__.py
index d9a9271f5..03aee5d0e 100644
--- a/fuelweb_test/__init__.py
+++ b/fuelweb_test/__init__.py
@@ -13,6 +13,7 @@
 #    under the License.
 import functools
 import logging
+import traceback
 import os
 from fuelweb_test.settings import LOGS_DIR
 
@@ -54,9 +55,17 @@ def debug(logger):
                     func.__name__, args, kwargs
                 )
             )
-            result = func(*args, **kwargs)
-            logger.debug(
-                "Done: {} with result: {}".format(func.__name__, result))
+            try:
+                result = func(*args, **kwargs)
+                logger.debug(
+                    "Done: {} with result: {}".format(func.__name__, result))
+            except BaseException as e:
+                tb = traceback.format_exc()
+                logger.error(
+                    '{func} raised: {exc!r}\n'
+                    'Traceback: {tb!s}'.format(
+                        func=func.__name__, exc=e, tb=tb))
+                raise
             return result
         return wrapped
     return wrapper
diff --git a/fuelweb_test/helpers/metaclasses.py b/fuelweb_test/helpers/metaclasses.py
new file mode 100644
index 000000000..6e1e79bcf
--- /dev/null
+++ b/fuelweb_test/helpers/metaclasses.py
@@ -0,0 +1,27 @@
+#    Copyright 2016 Mirantis, Inc.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+
+class SingletonMeta(type):
+    """Metaclass for Singleton
+
+    Main goals: not need to implement __new__ in singleton classes
+    """
+    _instances = {}
+
+    def __call__(cls, *args, **kwargs):
+        if cls not in cls._instances:
+            cls._instances[cls] = super(
+                SingletonMeta, cls).__call__(*args, **kwargs)
+        return cls._instances[cls]
diff --git a/fuelweb_test/helpers/ssh_manager.py b/fuelweb_test/helpers/ssh_manager.py
index 9fff6887e..55a35457a 100644
--- a/fuelweb_test/helpers/ssh_manager.py
+++ b/fuelweb_test/helpers/ssh_manager.py
@@ -1,4 +1,4 @@
-#    Copyright 2015 Mirantis, Inc.
+#    Copyright 2016 Mirantis, Inc.
 #
 #    Licensed under the Apache License, Version 2.0 (the "License"); you may
 #    not use this file except in compliance with the License. You may obtain
@@ -20,32 +20,27 @@ import json
 from paramiko import RSAKey
 from devops.models.node import SSHClient
 from fuelweb_test import logger
-
-
-class SingletonMeta(type):
-    def __init__(cls, name, bases, dict):
-        super(SingletonMeta, cls).__init__(name, bases, dict)
-        cls.instance = None
-
-    def __call__(self, *args, **kw):
-        if self.instance is None:
-            self.instance = super(SingletonMeta, self).__call__(*args, **kw)
-        return self.instance
-
-    def __getattr__(cls, name):
-        return getattr(cls(), name)
+from fuelweb_test.helpers import metaclasses
 
 
 class SSHManager(object):
-    __metaclass__ = SingletonMeta
+    __metaclass__ = metaclasses.SingletonMeta
+    # Slots is used to prevent uncontrolled attributes set or remove.
+    __slots__ = [
+        '__connections', 'admin_ip', 'admin_port', 'login', '__password'
+    ]
 
     def __init__(self):
         logger.debug('SSH_MANAGER: Run constructor SSHManager')
-        self.connections = {}
+        self.__connections = {}  # Disallow direct type change and deletion
         self.admin_ip = None
         self.admin_port = None
         self.login = None
-        self.password = None
+        self.__password = None
+
+    @property
+    def connections(self):
+        return self.__connections
 
     def initialize(self, admin_ip, login, password):
         """ It will be moved to __init__
@@ -58,7 +53,7 @@ class SSHManager(object):
         self.admin_ip = admin_ip
         self.admin_port = 22
         self.login = login
-        self.password = password
+        self.__password = password
 
     def _connect(self, remote):
         """ Check if connection is stable and return this one
@@ -97,7 +92,7 @@ class SSHManager(object):
                 host=ip,
                 port=port,
                 username=self.login,
-                password=self.password,
+                password=self.__password,
                 private_keys=keys
             )
         logger.debug('SSH_MANAGER:Return existed connection for '
@@ -192,6 +187,10 @@ class SSHManager(object):
 
         return result
 
+    def execute_async_on_remote(self, ip, cmd, port=22):
+        remote = self._get_remote(ip=ip, port=port)
+        return remote.execute_async(cmd)
+
     def _json_deserialize(self, json_string):
         """ Deserialize json_string and return object
 
diff --git a/fuelweb_test/models/environment.py b/fuelweb_test/models/environment.py
index 165ad8f64..0e4947d50 100644
--- a/fuelweb_test/models/environment.py
+++ b/fuelweb_test/models/environment.py
@@ -28,6 +28,7 @@ from proboscis.asserts import assert_true
 from fuelweb_test.helpers.decorators import revert_info
 from fuelweb_test.helpers.decorators import update_rpm_packages
 from fuelweb_test.helpers.decorators import upload_manifests
+from fuelweb_test.helpers.metaclasses import SingletonMeta
 from fuelweb_test.helpers.eb_tables import Ebtables
 from fuelweb_test.helpers.fuel_actions import AdminActions
 from fuelweb_test.helpers.fuel_actions import BaseActions
@@ -51,13 +52,7 @@ from fuelweb_test import logger
 class EnvironmentModel(object):
     """EnvironmentModel."""  # TODO documentation
 
-    _instance = None
-
-    def __new__(cls, *args, **kwargs):
-        if not cls._instance:
-            cls._instance = super(EnvironmentModel, cls).__new__(
-                cls, *args, **kwargs)
-        return cls._instance
+    __metaclass__ = SingletonMeta
 
     def __init__(self, config=None):
         if not hasattr(self, "_virt_env"):