diff --git a/tempest/api/compute/base.py b/tempest/api/compute/base.py
index a38dcd1..8ba074e 100644
--- a/tempest/api/compute/base.py
+++ b/tempest/api/compute/base.py
@@ -22,7 +22,6 @@
 from tempest.common import log as logging
 from tempest.common.utils.data_utils import parse_image_id
 from tempest.common.utils.data_utils import rand_name
-from tempest import exceptions
 import tempest.test
 
 
@@ -82,101 +81,6 @@
         cls.servers_client_v3_auth = os.servers_client_v3_auth
 
     @classmethod
-    def _get_identity_admin_client(cls):
-        """
-        Returns an instance of the Identity Admin API client
-        """
-        os = clients.AdminManager(interface=cls._interface)
-        admin_client = os.identity_client
-        return admin_client
-
-    @classmethod
-    def _get_client_args(cls):
-
-        return (
-            cls.config,
-            cls.config.identity.admin_username,
-            cls.config.identity.admin_password,
-            cls.config.identity.uri
-        )
-
-    @classmethod
-    def _get_isolated_creds(cls, admin=False):
-        """
-        Creates a new set of user/tenant/password credentials for a
-        **regular** user of the Compute API so that a test case can
-        operate in an isolated tenant container.
-        """
-        admin_client = cls._get_identity_admin_client()
-        password = "pass"
-
-        while True:
-            try:
-                rand_name_root = rand_name(cls.__name__)
-                if cls.isolated_creds:
-                # Main user already created. Create the alt one...
-                    rand_name_root += '-alt'
-                tenant_name = rand_name_root + "-tenant"
-                tenant_desc = tenant_name + "-desc"
-
-                resp, tenant = admin_client.create_tenant(
-                    name=tenant_name, description=tenant_desc)
-                break
-            except exceptions.Duplicate:
-                if cls.config.compute.allow_tenant_reuse:
-                    tenant = admin_client.get_tenant_by_name(tenant_name)
-                    LOG.info('Re-using existing tenant %s', tenant)
-                    break
-
-        while True:
-            try:
-                rand_name_root = rand_name(cls.__name__)
-                if cls.isolated_creds:
-                # Main user already created. Create the alt one...
-                    rand_name_root += '-alt'
-                username = rand_name_root + "-user"
-                email = rand_name_root + "@example.com"
-                resp, user = admin_client.create_user(username,
-                                                      password,
-                                                      tenant['id'],
-                                                      email)
-                break
-            except exceptions.Duplicate:
-                if cls.config.compute.allow_tenant_reuse:
-                    user = admin_client.get_user_by_username(tenant['id'],
-                                                             username)
-                    LOG.info('Re-using existing user %s', user)
-                    break
-        # Store the complete creds (including UUID ids...) for later
-        # but return just the username, tenant_name, password tuple
-        # that the various clients will use.
-        cls.isolated_creds.append((user, tenant))
-
-        # Assign admin role if this is for admin creds
-        if admin:
-            _, roles = admin_client.list_roles()
-            role = None
-            try:
-                _, roles = admin_client.list_roles()
-                role = next(r for r in roles if r['name'] == 'admin')
-            except StopIteration:
-                msg = "No admin role found"
-                raise exceptions.NotFound(msg)
-            admin_client.assign_user_role(tenant['id'], user['id'], role['id'])
-
-        return username, tenant_name, password
-
-    @classmethod
-    def clear_isolated_creds(cls):
-        if not cls.isolated_creds:
-            return
-        admin_client = cls._get_identity_admin_client()
-
-        for user, tenant in cls.isolated_creds:
-            admin_client.delete_user(user['id'])
-            admin_client.delete_tenant(tenant['id'])
-
-    @classmethod
     def clear_servers(cls):
         for server in cls.servers:
             try:
@@ -204,7 +108,7 @@
     def tearDownClass(cls):
         cls.clear_images()
         cls.clear_servers()
-        cls.clear_isolated_creds()
+        cls._clear_isolated_creds()
 
     @classmethod
     def create_server(cls, **kwargs):
diff --git a/tempest/api/volume/base.py b/tempest/api/volume/base.py
index 5770d28..a84f9e8 100644
--- a/tempest/api/volume/base.py
+++ b/tempest/api/volume/base.py
@@ -19,7 +19,6 @@
 
 from tempest import clients
 from tempest.common import log as logging
-from tempest.common.utils.data_utils import rand_name
 import tempest.test
 
 LOG = logging.getLogger(__name__)
@@ -65,59 +64,10 @@
                                          cls.os.tenant_name)
 
     @classmethod
-    def _get_identity_admin_client(cls):
-        """
-        Returns an instance of the Identity Admin API client
-        """
-        os = clients.ComputeAdminManager()
-        return os.identity_client
-
-    @classmethod
-    def _get_isolated_creds(cls):
-        """
-        Creates a new set of user/tenant/password credentials for a
-        **regular** user of the Volume API so that a test case can
-        operate in an isolated tenant container.
-        """
-        admin_client = cls._get_identity_admin_client()
-        rand_name_root = rand_name(cls.__name__)
-        if cls.isolated_creds:
-            # Main user already created. Create the alt one...
-            rand_name_root += '-alt'
-        username = rand_name_root + "-user"
-        email = rand_name_root + "@example.com"
-        tenant_name = rand_name_root + "-tenant"
-        tenant_desc = tenant_name + "-desc"
-        password = "pass"
-
-        resp, tenant = admin_client.create_tenant(name=tenant_name,
-                                                  description=tenant_desc)
-        resp, user = admin_client.create_user(username,
-                                              password,
-                                              tenant['id'],
-                                              email)
-        # Store the complete creds (including UUID ids...) for later
-        # but return just the username, tenant_name, password tuple
-        # that the various clients will use.
-        cls.isolated_creds.append((user, tenant))
-
-        return username, tenant_name, password
-
-    @classmethod
-    def clear_isolated_creds(cls):
-        if not cls.isolated_creds:
-            return
-        admin_client = cls._get_identity_admin_client()
-
-        for user, tenant in cls.isolated_creds:
-            admin_client.delete_user(user['id'])
-            admin_client.delete_tenant(tenant['id'])
-
-    @classmethod
     def tearDownClass(cls):
         cls.clear_snapshots()
         cls.clear_volumes()
-        cls.clear_isolated_creds()
+        cls._clear_isolated_creds()
 
     @classmethod
     def create_snapshot(cls, volume_id=1, **kwargs):
@@ -198,6 +148,13 @@
             msg = ("Missing Volume Admin API credentials "
                    "in configuration.")
             raise cls.skipException(msg)
-
-        cls.os_adm = clients.AdminManager(interface=cls._interface)
+        if cls.config.compute.allow_tenant_isolation:
+            creds = cls._get_isolated_creds(admin=True)
+            admin_username, admin_tenant_name, admin_password = creds
+            cls.os_adm = clients.Manager(username=admin_username,
+                                         password=admin_password,
+                                         tenant_name=admin_tenant_name,
+                                         interface=cls._interface)
+        else:
+            cls.os_adm = clients.AdminManager(interface=cls._interface)
         cls.client = cls.os_adm.volume_types_client
diff --git a/tempest/config.py b/tempest/config.py
index 68acdaa..eeb7b9d 100644
--- a/tempest/config.py
+++ b/tempest/config.py
@@ -292,7 +292,7 @@
                default="10.100.0.0/16",
                help="The cidr block to allocate tenant networks from"),
     cfg.IntOpt('tenant_network_mask_bits',
-               default=29,
+               default=28,
                help="The mask bits for tenant networks"),
     cfg.BoolOpt('tenant_networks_reachable',
                 default=False,
diff --git a/tempest/test.py b/tempest/test.py
index d7008a7..d151c84 100644
--- a/tempest/test.py
+++ b/tempest/test.py
@@ -21,8 +21,11 @@
 import testresources
 import testtools
 
+from tempest import clients
 from tempest.common import log as logging
+from tempest.common.utils.data_utils import rand_name
 from tempest import config
+from tempest import exceptions
 from tempest import manager
 
 LOG = logging.getLogger(__name__)
@@ -65,6 +68,104 @@
         if hasattr(super(BaseTestCase, cls), 'setUpClass'):
             super(BaseTestCase, cls).setUpClass()
 
+    @classmethod
+    def _get_identity_admin_client(cls):
+        """
+        Returns an instance of the Identity Admin API client
+        """
+        os = clients.AdminManager(interface=cls._interface)
+        admin_client = os.identity_client
+        return admin_client
+
+    @classmethod
+    def _get_client_args(cls):
+
+        return (
+            cls.config,
+            cls.config.identity.admin_username,
+            cls.config.identity.admin_password,
+            cls.config.identity.uri
+        )
+
+    @classmethod
+    def _get_isolated_creds(cls, admin=False):
+        """
+        Creates a new set of user/tenant/password credentials for a
+        **regular** user of the Compute API so that a test case can
+        operate in an isolated tenant container.
+        """
+        admin_client = cls._get_identity_admin_client()
+        password = "pass"
+
+        while True:
+            try:
+                rand_name_root = rand_name(cls.__name__)
+                if cls.isolated_creds:
+                # Main user already created. Create the alt or admin one...
+                    if admin:
+                        rand_name_root += '-admin'
+                    else:
+                        rand_name_root += '-alt'
+                tenant_name = rand_name_root + "-tenant"
+                tenant_desc = tenant_name + "-desc"
+
+                resp, tenant = admin_client.create_tenant(
+                    name=tenant_name, description=tenant_desc)
+                break
+            except exceptions.Duplicate:
+                if cls.config.compute.allow_tenant_reuse:
+                    tenant = admin_client.get_tenant_by_name(tenant_name)
+                    LOG.info('Re-using existing tenant %s', tenant)
+                    break
+
+        while True:
+            try:
+                rand_name_root = rand_name(cls.__name__)
+                if cls.isolated_creds:
+                # Main user already created. Create the alt one...
+                    rand_name_root += '-alt'
+                username = rand_name_root + "-user"
+                email = rand_name_root + "@example.com"
+                resp, user = admin_client.create_user(username,
+                                                      password,
+                                                      tenant['id'],
+                                                      email)
+                break
+            except exceptions.Duplicate:
+                if cls.config.compute.allow_tenant_reuse:
+                    user = admin_client.get_user_by_username(tenant['id'],
+                                                             username)
+                    LOG.info('Re-using existing user %s', user)
+                    break
+        # Store the complete creds (including UUID ids...) for later
+        # but return just the username, tenant_name, password tuple
+        # that the various clients will use.
+        cls.isolated_creds.append((user, tenant))
+
+        # Assign admin role if this is for admin creds
+        if admin:
+            _, roles = admin_client.list_roles()
+            role = None
+            try:
+                _, roles = admin_client.list_roles()
+                role = next(r for r in roles if r['name'] == 'admin')
+            except StopIteration:
+                msg = "No admin role found"
+                raise exceptions.NotFound(msg)
+            admin_client.assign_user_role(tenant['id'], user['id'], role['id'])
+
+        return username, tenant_name, password
+
+    @classmethod
+    def _clear_isolated_creds(cls):
+        if not cls.isolated_creds:
+            return
+        admin_client = cls._get_identity_admin_client()
+
+        for user, tenant in cls.isolated_creds:
+            admin_client.delete_user(user['id'])
+            admin_client.delete_tenant(tenant['id'])
+
 
 def call_until_true(func, duration, sleep_for):
     """