Use rand name in common function in scenario tests

There already exists rand name in common functions in scenario.
manager.py, so some rand name definitions can be removed to
keep code clean.

Change-Id: I1f5cd7dab8bffad31bcebea1f8ad97fb53c67ef9
diff --git a/tempest/scenario/manager.py b/tempest/scenario/manager.py
index 3a808ce..ab388c2 100644
--- a/tempest/scenario/manager.py
+++ b/tempest/scenario/manager.py
@@ -216,7 +216,7 @@
         if size is None:
             size = CONF.volume.volume_size
         if name is None:
-            name = data_utils.rand_name(self.__class__.__name__)
+            name = data_utils.rand_name(self.__class__.__name__ + "-volume")
         kwargs = {'display_name': name,
                   'snapshot_id': snapshot_id,
                   'imageRef': imageRef,
@@ -417,7 +417,7 @@
         # Compute client
         _images_client = self.compute_images_client
         if name is None:
-            name = data_utils.rand_name('scenario-snapshot')
+            name = data_utils.rand_name(self.__class__.__name__ + 'snapshot')
         LOG.debug("Creating a snapshot image for server: %s", server['name'])
         image = _images_client.create_image(server['id'], name=name)
         image_id = image.response['location'].split('images/')[1]
diff --git a/tempest/scenario/test_network_advanced_server_ops.py b/tempest/scenario/test_network_advanced_server_ops.py
index 3390aff..2ae067e 100644
--- a/tempest/scenario/test_network_advanced_server_ops.py
+++ b/tempest/scenario/test_network_advanced_server_ops.py
@@ -15,7 +15,6 @@
 
 import testtools
 
-from tempest.common.utils import data_utils
 from tempest.common import waiters
 from tempest import config
 from tempest.scenario import manager
@@ -56,9 +55,7 @@
             security_group = self._create_security_group()
             security_groups = [{'name': security_group['name']}]
         network, subnet, router = self.create_networks()
-        server_name = data_utils.rand_name(self.__class__.__name__ + '-server')
         server = self.create_server(
-            name=server_name,
             networks=[{'uuid': network['id']}],
             key_name=keypair['name'],
             security_groups=security_groups,
diff --git a/tempest/scenario/test_volume_boot_pattern.py b/tempest/scenario/test_volume_boot_pattern.py
index 44ad136..db5e009 100644
--- a/tempest/scenario/test_volume_boot_pattern.py
+++ b/tempest/scenario/test_volume_boot_pattern.py
@@ -88,11 +88,6 @@
 
         return snap
 
-    def _create_volume_from_snapshot(self, snap_id):
-        vol_name = data_utils.rand_name(
-            self.__class__.__name__ + '-volume')
-        return self.create_volume(name=vol_name, snapshot_id=snap_id)
-
     def _delete_server(self, server):
         self.servers_client.delete_server(server['id'])
         waiters.wait_for_server_termination(self.servers_client, server['id'])
@@ -153,7 +148,7 @@
 
         # create a 3rd instance from snapshot
         LOG.info("Creating third instance from snapshot: %s" % snapshot['id'])
-        volume = self._create_volume_from_snapshot(snapshot['id'])
+        volume = self.create_volume(snapshot_id=snapshot['id'])
         server_from_snapshot = (
             self._boot_instance_from_volume(volume['id'],
                                             keypair, security_group))
@@ -174,8 +169,7 @@
         instance = self._boot_instance_from_volume(volume_origin['id'],
                                                    delete_on_termination=True)
         # create EBS image
-        name = data_utils.rand_name(self.__class__.__name__ + '-image')
-        image = self.create_server_snapshot(instance, name=name)
+        image = self.create_server_snapshot(instance)
 
         # delete instance
         self._delete_server(instance)