Remove instance Foreign Key in volumes table, replace with instance_uuid

* Remove the instance relationship and instance_id FK
* Add instance_uuuid column to volumes table
* Passed unit tests and devstack tests

Change-Id: Id598f1f1d7915d1af6bf3dd75e5819dce08aaa0f

21 files changed, 456 insertions, 94 deletions

diff --git a/etc/nova/nova.conf.sample b/etc/nova/nova.conf.sample
index 027472310..02ccf265d 100644
--- a/etc/nova/nova.conf.sample
+++ b/etc/nova/nova.conf.sample
@@ -311,7 +311,7 @@
 ###### (StrOpt) Template string to be used to generate snapshot names
 # snapshot_name_template="snapshot-%08x"
 ###### (StrOpt) Template string to be used to generate instance names
-# volume_name_template="volume-%08x"
+# volume_name_template="volume-%s"
 
 ######### defined in nova.crypto #########
 
diff --git a/nova/api/ec2/ec2utils.py b/nova/api/ec2/ec2utils.py
index 9006da93e..ceb695a5e 100644
--- a/nova/api/ec2/ec2utils.py
+++ b/nova/api/ec2/ec2utils.py
@@ -197,6 +197,10 @@ def get_snapshot_uuid_from_int_id(context, int_id):
     return db.get_snapshot_uuid_by_ec2_id(context, int_id)
 
 
+def ec2_instance_id_to_uuid(context, ec2_id):
+    int_id = ec2_id_to_id(ec2_id)
+    return db.instance_get(context, int_id)['uuid']
+
 _c2u = re.compile('(((?<=[a-z])[A-Z])|([A-Z](?![A-Z]|$)))')
 
 
diff --git a/nova/api/openstack/compute/contrib/volumes.py b/nova/api/openstack/compute/contrib/volumes.py
index 129b181c7..004a667b1 100644
--- a/nova/api/openstack/compute/contrib/volumes.py
+++ b/nova/api/openstack/compute/contrib/volumes.py
@@ -371,10 +371,9 @@ class VolumeAttachmentController(object):
         except exception.NotFound:
             raise exc.HTTPNotFound()
 
-        instance = vol['instance']
-        if instance is None or str(instance['uuid']) != server_id:
-            LOG.debug("Instance not found (server_id=%(server_id)s)",
-                      {'server_id': server_id}, instance=instance)
+        instance_uuid = vol['instance_uuid']
+        if instance_uuid is None or instance_uuid != server_id:
+            LOG.debug(_("Instance %s is not attached."), instance_uuid)
             raise exc.HTTPNotFound()
 
         self.compute_api.detach_volume(context,
diff --git a/nova/api/openstack/volume/volumes.py b/nova/api/openstack/volume/volumes.py
index 7789bc1aa..5da007d13 100644
--- a/nova/api/openstack/volume/volumes.py
+++ b/nova/api/openstack/volume/volumes.py
@@ -48,15 +48,13 @@ def _translate_attachment_summary_view(_context, vol):
     """Maps keys for attachment summary view."""
     d = {}
 
-    # TODO(bcwaldon): remove str cast once we use uuids
-    volume_id = str(vol['id'])
+    volume_id = vol['id']
 
     # NOTE(justinsb): We use the volume id as the id of the attachment object
     d['id'] = volume_id
 
     d['volume_id'] = volume_id
-    if vol.get('instance'):
-        d['server_id'] = vol['instance']['uuid']
+    d['server_id'] = vol['instance_uuid']
     if vol.get('mountpoint'):
         d['device'] = vol['mountpoint']
 
@@ -77,8 +75,7 @@ def _translate_volume_summary_view(context, vol):
     """Maps keys for volumes summary view."""
     d = {}
 
-    # TODO(bcwaldon): remove str cast once we use uuids
-    d['id'] = str(vol['id'])
+    d['id'] = vol['id']
     d['status'] = vol['status']
     d['size'] = vol['size']
     d['availability_zone'] = vol['availability_zone']
@@ -99,9 +96,6 @@ def _translate_volume_summary_view(context, vol):
         d['volume_type'] = str(vol['volume_type_id'])
 
     d['snapshot_id'] = vol['snapshot_id']
-    # TODO(bcwaldon): remove str cast once we use uuids
-    if d['snapshot_id'] is not None:
-        d['snapshot_id'] = str(d['snapshot_id'])
 
     LOG.audit(_("vol=%s"), vol, context=context)
 
diff --git a/nova/compute/api.py b/nova/compute/api.py
index 32b7d79ce..5e1426fce 100644
--- a/nova/compute/api.py
+++ b/nova/compute/api.py
@@ -1654,7 +1654,10 @@ class API(BaseAPI):
     # the volume ID via volume API and pass it and the volume object here
     def detach_volume(self, context, volume_id):
         """Detach a volume from an instance."""
-        instance = self.db.volume_get_instance(context.elevated(), volume_id)
+        volume = self.volume_api.get(context, volume_id)
+        instance_uuid = volume['instance_uuid']
+        instance = self.db.instance_get_by_uuid(context.elevated(),
+                                                instance_uuid)
         if not instance:
             raise exception.VolumeUnattached(volume_id=volume_id)
 
diff --git a/nova/compute/manager.py b/nova/compute/manager.py
index 382464e7d..d558144ed 100644
--- a/nova/compute/manager.py
+++ b/nova/compute/manager.py
@@ -67,7 +67,6 @@ from nova.openstack.common import importutils
 from nova import rpc
 from nova import utils
 from nova.virt import driver
-from nova import vnc
 from nova import volume
 
 
@@ -261,7 +260,6 @@ class ComputeManager(manager.SchedulerDependentManager):
         context = nova.context.get_admin_context()
         instances = self.db.instance_get_all_by_host(context, self.host)
         for instance in instances:
-            instance_uuid = instance['uuid']
             db_state = instance['power_state']
             drv_state = self._get_power_state(context, instance)
 
@@ -1725,7 +1723,7 @@ class ComputeManager(manager.SchedulerDependentManager):
         connection_info = self.volume_api.initialize_connection(context,
                                                                 volume,
                                                                 connector)
-        self.volume_api.attach(context, volume, instance_id, mountpoint)
+        self.volume_api.attach(context, volume, instance_uuid, mountpoint)
         return connection_info
 
     @exception.wrap_exception(notifier=notifier, publisher_id=publisher_id())
@@ -1764,7 +1762,10 @@ class ComputeManager(manager.SchedulerDependentManager):
                                                      volume,
                                                      connector)
 
-        self.volume_api.attach(context, volume, instance_ref['id'], mountpoint)
+        self.volume_api.attach(context,
+                               volume,
+                               instance_ref['uuid'],
+                               mountpoint)
         values = {
             'instance_uuid': instance_ref['uuid'],
             'connection_info': utils.dumps(connection_info),
diff --git a/nova/db/api.py b/nova/db/api.py
index 93eea8f10..ca1e420d7 100644
--- a/nova/db/api.py
+++ b/nova/db/api.py
@@ -986,9 +986,9 @@ def volume_get_all_by_host(context, host):
     return IMPL.volume_get_all_by_host(context, host)
 
 
-def volume_get_all_by_instance(context, instance_id):
+def volume_get_all_by_instance_uuid(context, instance_uuid):
     """Get all volumes belonging to a instance."""
-    return IMPL.volume_get_all_by_instance(context, instance_id)
+    return IMPL.volume_get_all_by_instance_uuid(context, instance_uuid)
 
 
 def volume_get_all_by_project(context, project_id):
@@ -1001,11 +1001,6 @@ def volume_get_by_ec2_id(context, ec2_id):
     return IMPL.volume_get_by_ec2_id(context, ec2_id)
 
 
-def volume_get_instance(context, volume_id):
-    """Get the instance that a volume is attached to."""
-    return IMPL.volume_get_instance(context, volume_id)
-
-
 def volume_get_iscsi_target_num(context, volume_id):
     """Get the target num (tid) allocated to the volume."""
     return IMPL.volume_get_iscsi_target_num(context, volume_id)
diff --git a/nova/db/sqlalchemy/api.py b/nova/db/sqlalchemy/api.py
index 46e080578..f6af98d68 100644
--- a/nova/db/sqlalchemy/api.py
+++ b/nova/db/sqlalchemy/api.py
@@ -1374,7 +1374,6 @@ def _build_instance_get(context, session=None):
                         project_only=True).\
             options(joinedload_all('security_groups.rules')).\
             options(joinedload('info_cache')).\
-            options(joinedload('volumes')).\
             options(joinedload('metadata')).\
             options(joinedload('instance_type'))
 
@@ -2402,15 +2401,17 @@ def volume_allocate_iscsi_target(context, volume_id, host):
 
 
 @require_admin_context
-def volume_attached(context, volume_id, instance_id, mountpoint):
+def volume_attached(context, volume_id, instance_uuid, mountpoint):
+    if not utils.is_uuid_like(instance_uuid):
+        raise exception.InvalidUUID(instance_uuid)
+
     session = get_session()
     with session.begin():
         volume_ref = volume_get(context, volume_id, session=session)
         volume_ref['status'] = 'in-use'
         volume_ref['mountpoint'] = mountpoint
         volume_ref['attach_status'] = 'attached'
-        volume_ref.instance = instance_get(context, instance_id,
-                                           session=session)
+        volume_ref['instance_uuid'] = instance_uuid
         volume_ref.save(session=session)
 
 
@@ -2471,7 +2472,7 @@ def volume_detached(context, volume_id):
         volume_ref['status'] = 'available'
         volume_ref['mountpoint'] = None
         volume_ref['attach_status'] = 'detached'
-        volume_ref.instance = None
+        volume_ref['instance_uuid'] = None
         volume_ref.save(session=session)
 
 
@@ -2479,9 +2480,8 @@ def volume_detached(context, volume_id):
 def _volume_get_query(context, session=None, project_only=False):
     return model_query(context, models.Volume, session=session,
                        project_only=project_only).\
-                     options(joinedload('instance')).\
-                     options(joinedload('volume_metadata')).\
-                     options(joinedload('volume_type'))
+                       options(joinedload('volume_metadata')).\
+                       options(joinedload('volume_type'))
 
 
 @require_context
@@ -2519,15 +2519,15 @@ def volume_get_all_by_host(context, host):
 
 
 @require_admin_context
-def volume_get_all_by_instance(context, instance_id):
+def volume_get_all_by_instance_uuid(context, instance_uuid):
     result = model_query(context, models.Volume, read_deleted="no").\
                      options(joinedload('volume_metadata')).\
                      options(joinedload('volume_type')).\
-                     filter_by(instance_id=instance_id).\
+                     filter_by(instance_uuid=instance_uuid).\
                      all()
 
     if not result:
-        raise exception.VolumeNotFoundForInstance(instance_id=instance_id)
+        return []
 
     return result
 
@@ -2539,16 +2539,6 @@ def volume_get_all_by_project(context, project_id):
 
 
 @require_admin_context
-def volume_get_instance(context, volume_id):
-    result = _volume_get_query(context).filter_by(id=volume_id).first()
-
-    if not result:
-        raise exception.VolumeNotFound(volume_id=volume_id)
-
-    return result.instance
-
-
-@require_admin_context
 def volume_get_iscsi_target_num(context, volume_id):
     result = model_query(context, models.IscsiTarget, read_deleted="yes").\
                      filter_by(volume_id=volume_id).\
diff --git a/nova/db/sqlalchemy/migrate_repo/versions/095_change_fk_instance_id_to_uuid.py b/nova/db/sqlalchemy/migrate_repo/versions/095_change_fk_instance_id_to_uuid.py
new file mode 100644
index 000000000..ea8684f3d
--- /dev/null
+++ b/nova/db/sqlalchemy/migrate_repo/versions/095_change_fk_instance_id_to_uuid.py
@@ -0,0 +1,94 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright 2012 OpenStack LLC.
+# Copyright 2012 SolidFire Inc
+# All Rights Reserved.
+#
+#    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.
+
+from sqlalchemy import select, Column
+from sqlalchemy import MetaData, Integer, String, Table
+from migrate import ForeignKeyConstraint
+
+from nova import log as logging
+
+
+LOG = logging.getLogger(__name__)
+
+
+def upgrade(migrate_engine):
+    meta = MetaData()
+    meta.bind = migrate_engine
+
+    instances = Table('instances', meta, autoload=True)
+    volumes = Table('volumes', meta, autoload=True)
+    instance_uuid_column = Column('instance_uuid', String(36))
+
+    instance_uuid_column.create(volumes)
+    try:
+        volumes.update().values(
+            instance_uuid=select(
+                [instances.c.uuid],
+                instances.c.id == volumes.c.instance_id)
+                ).execute()
+    except Exception:
+        instance_uuid_column.drop()
+
+    fkeys = list(volumes.c.instance_id.foreign_keys)
+    if fkeys:
+        try:
+            fk_name = fkeys[0].constraint.name
+            ForeignKeyConstraint(
+                columns=[volumes.c.instance_id],
+                refcolumns=[instances.c.id],
+                name=fk_name).drop()
+
+        except Exception:
+            LOG.error(_("foreign key could not be dropped"))
+            raise
+
+    volumes.c.instance_id.drop()
+
+
+def downgrade(migrate_engine):
+    meta = MetaData()
+    meta.bind = migrate_engine
+
+    instances = Table('instances', meta, autoload=True)
+    volumes = Table('volumes', meta, autoload=True)
+    instance_id_column = Column('instance_id', Integer)
+
+    instance_id_column.create(volumes)
+    try:
+        volumes.update().values(
+            instance_id=select(
+                [instances.c.id],
+                instances.c.uuid == volumes.c.instance_uuid)
+                ).execute()
+    except Exception:
+        instance_id_column.drop()
+
+    fkeys = list(volumes.c.instance_id.foreign_keys)
+    if fkeys:
+        try:
+            fk_name = fkeys[0].constraint.name
+            ForeignKeyConstraint(
+                columns=[volumes.c.instance_id],
+                refcolumns=[instances.c.id],
+                name=fk_name).create()
+
+        except Exception:
+            LOG.error(_("foreign key could not be created"))
+            raise
+
+    volumes.c.instance_uuid.drop()
diff --git a/nova/db/sqlalchemy/migrate_repo/versions/095_sqlite_downgrade.sql b/nova/db/sqlalchemy/migrate_repo/versions/095_sqlite_downgrade.sql
new file mode 100644
index 000000000..7c13455e4
--- /dev/null
+++ b/nova/db/sqlalchemy/migrate_repo/versions/095_sqlite_downgrade.sql
@@ -0,0 +1,133 @@
+BEGIN TRANSACTION;
+    -- change instance_id volumes table
+    CREATE TABLE volumes_backup(
+        created_at DATETIME,
+        updated_at DATETIME,
+        deleted_at DATETIME,
+        deleted BOOLEAN,
+        id VARCHAR(36) NOT NULL,
+        ec2_id INTEGER,
+        user_id VARCHAR(255),
+        project_id VARCHAR(255),
+        snapshot_id VARCHAR(36),
+        host VARCHAR(255),
+        size INTEGER,
+        availability_zone VARCHAR(255),
+        instance_id INTEGER,
+        instance_uuid VARCHAR(36),
+        mountpoint VARCHAR(255),
+        attach_time VARCHAR(255),
+        status VARCHAR(255),
+        attach_status VARCHAR(255),
+        scheduled_at DATETIME,
+        launched_at DATETIME,
+        terminated_at DATETIME,
+        display_name VARCHAR(255),
+        display_description VARCHAR(255),
+        provider_location VARCHAR(255),
+        provider_auth VARCHAR(255),
+        volume_type_id INTEGER,
+        PRIMARY KEY (id),
+        FOREIGN KEY(instance_id) REFERENCES instances (id),
+        UNIQUE (id),
+        CHECK (deleted IN (0, 1))
+    );
+
+    INSERT INTO volumes_backup SELECT
+        created_at,
+        updated_at,
+        deleted_at,
+        deleted,
+        id,
+        ec2_id,
+        user_id,
+        project_id,
+        snapshot_id,
+        host,
+        size,
+        availability_zone,
+        NULL,
+        instance_uuid,
+        mountpoint,
+        attach_time,
+        status,
+        attach_status,
+        scheduled_at,
+        launched_at,
+        terminated_at,
+        display_name,
+        display_description,
+        provider_location,
+        provider_auth,
+        volume_type_id
+    FROM volumes;
+
+    UPDATE volumes_backup
+        SET instance_id =
+            (SELECT id
+                FROM instances
+                WHERE volumes_backup.instance_uuid = instances.uuid
+        );
+    DROP TABLE volumes;
+
+    CREATE TABLE volumes(
+        created_at DATETIME,
+        updated_at DATETIME,
+        deleted_at DATETIME,
+        deleted BOOLEAN,
+        id VARCHAR(36) NOT NULL,
+        ec2_id INTEGER,
+        user_id VARCHAR(255),
+        project_id VARCHAR(255),
+        snapshot_id VARCHAR(36),
+        host VARCHAR(255),
+        size INTEGER,
+        availability_zone VARCHAR(255),
+        instance_id INTEGER,
+        mountpoint VARCHAR(255),
+        attach_time VARCHAR(255),
+        status VARCHAR(255),
+        attach_status VARCHAR(255),
+        scheduled_at DATETIME,
+        launched_at DATETIME,
+        terminated_at DATETIME,
+        display_name VARCHAR(255),
+        display_description VARCHAR(255),
+        provider_location VARCHAR(255),
+        provider_auth VARCHAR(255),
+        volume_type_id INTEGER,
+        PRIMARY KEY (id),
+        FOREIGN KEY (instance_id) REFERENCES instances (id),
+        UNIQUE (id),
+        CHECK (deleted IN (0, 1))
+    );
+
+    INSERT INTO volumes
+        SELECT created_at,
+               updated_at,
+               deleted_at,
+               deleted,
+               id,
+               ec2_id,
+               user_id,
+               project_id,
+               snapshot_id,
+               host,
+               size,
+               availability_zone,
+               instance_id,
+               mountpoint,
+               attach_time,
+               status,
+               attach_status,
+               scheduled_at,
+               launched_at,
+               terminated_at,
+               display_name,
+               display_description,
+               provider_location,
+               provider_auth,
+               volume_type_id
+        FROM volumes_backup;
+    DROP TABLE volumes_backup;
+COMMIT;
diff --git a/nova/db/sqlalchemy/migrate_repo/versions/095_sqlite_upgrade.sql b/nova/db/sqlalchemy/migrate_repo/versions/095_sqlite_upgrade.sql
new file mode 100644
index 000000000..130e11030
--- /dev/null
+++ b/nova/db/sqlalchemy/migrate_repo/versions/095_sqlite_upgrade.sql
@@ -0,0 +1,132 @@
+BEGIN TRANSACTION;
+    -- change instance_id volumes table
+    CREATE TABLE volumes_backup(
+        created_at DATETIME,
+        updated_at DATETIME,
+        deleted_at DATETIME,
+        deleted BOOLEAN,
+        id VARCHAR(36) NOT NULL,
+        ec2_id INTEGER,
+        user_id VARCHAR(255),
+        project_id VARCHAR(255),
+        snapshot_id VARCHAR(36),
+        host VARCHAR(255),
+        size INTEGER,
+        availability_zone VARCHAR(255),
+        instance_id INTEGER,
+        instance_uuid VARCHAR(36),
+        mountpoint VARCHAR(255),
+        attach_time VARCHAR(255),
+        status VARCHAR(255),
+        attach_status VARCHAR(255),
+        scheduled_at DATETIME,
+        launched_at DATETIME,
+        terminated_at DATETIME,
+        display_name VARCHAR(255),
+        display_description VARCHAR(255),
+        provider_location VARCHAR(255),
+        provider_auth VARCHAR(255),
+        volume_type_id INTEGER,
+        PRIMARY KEY (id),
+        FOREIGN KEY(instance_id) REFERENCES instances (id),
+        UNIQUE (id),
+        CHECK (deleted IN (0, 1))
+    );
+
+    INSERT INTO volumes_backup SELECT
+        created_at,
+        updated_at,
+        deleted_at,
+        deleted,
+        id,
+        ec2_id,
+        user_id,
+        project_id,
+        snapshot_id,
+        host,
+        size,
+        availability_zone,
+        instance_id,
+        NULL,
+        mountpoint,
+        attach_time,
+        status,
+        attach_status,
+        scheduled_at,
+        launched_at,
+        terminated_at,
+        display_name,
+        display_description,
+        provider_location,
+        provider_auth,
+        volume_type_id
+    FROM volumes;
+
+    UPDATE volumes_backup
+        SET instance_uuid =
+            (SELECT uuid
+                FROM instances
+                WHERE volumes_backup.instance_id = instances.id
+        );
+    DROP TABLE volumes;
+
+    CREATE TABLE volumes(
+        created_at DATETIME,
+        updated_at DATETIME,
+        deleted_at DATETIME,
+        deleted BOOLEAN,
+        id VARCHAR(36) NOT NULL,
+        ec2_id INTEGER,
+        user_id VARCHAR(255),
+        project_id VARCHAR(255),
+        snapshot_id VARCHAR(36),
+        host VARCHAR(255),
+        size INTEGER,
+        availability_zone VARCHAR(255),
+        instance_uuid VARCHAR(36),
+        mountpoint VARCHAR(255),
+        attach_time VARCHAR(255),
+        status VARCHAR(255),
+        attach_status VARCHAR(255),
+        scheduled_at DATETIME,
+        launched_at DATETIME,
+        terminated_at DATETIME,
+        display_name VARCHAR(255),
+        display_description VARCHAR(255),
+        provider_location VARCHAR(255),
+        provider_auth VARCHAR(255),
+        volume_type_id INTEGER,
+        PRIMARY KEY (id),
+        UNIQUE (id),
+        CHECK (deleted IN (0, 1))
+    );
+
+    INSERT INTO volumes
+        SELECT created_at,
+               updated_at,
+               deleted_at,
+               deleted,
+               id,
+               ec2_id,
+               user_id,
+               project_id,
+               snapshot_id,
+               host,
+               size,
+               availability_zone,
+               instance_uuid,
+               mountpoint,
+               attach_time,
+               status,
+               attach_status,
+               scheduled_at,
+               launched_at,
+               terminated_at,
+               display_name,
+               display_description,
+               provider_location,
+               provider_auth,
+               volume_type_id
+        FROM volumes_backup;
+    DROP TABLE volumes_backup;
+COMMIT;
diff --git a/nova/db/sqlalchemy/models.py b/nova/db/sqlalchemy/models.py
index 9007de424..056ecd411 100644
--- a/nova/db/sqlalchemy/models.py
+++ b/nova/db/sqlalchemy/models.py
@@ -341,12 +341,7 @@ class Volume(BASE, NovaBase):
     host = Column(String(255))  # , ForeignKey('hosts.id'))
     size = Column(Integer)
     availability_zone = Column(String(255))  # TODO(vish): foreign key?
-    instance_id = Column(Integer, ForeignKey('instances.id'), nullable=True)
-    instance = relationship(Instance,
-                            backref=backref('volumes'),
-                            foreign_keys=instance_id,
-                            primaryjoin='and_(Volume.instance_id==Instance.id,'
-                                             'Volume.deleted==False)')
+    instance_uuid = Column(String(36))
     mountpoint = Column(String(255))
     attach_time = Column(String(255))  # TODO(vish): datetime
     status = Column(String(255))  # TODO(vish): enum?
diff --git a/nova/exception.py b/nova/exception.py
index d724063ef..c97290480 100644
--- a/nova/exception.py
+++ b/nova/exception.py
@@ -26,7 +26,6 @@ SHOULD include dedicated exception logging.
 
 import functools
 import itertools
-import sys
 
 import webob.exc
 
@@ -420,6 +419,10 @@ class InvalidEc2Id(Invalid):
     message = _("Ec2 id %(ec2_id)s is unacceptable.")
 
 
+class InvalidUUID(Invalid):
+    message = _("Expected a uuid but received %(uuid).")
+
+
 class NotFound(NovaException):
     message = _("Resource could not be found.")
     code = 404
diff --git a/nova/tests/api/ec2/test_cloud.py b/nova/tests/api/ec2/test_cloud.py
index 6d312369b..ec8bdf276 100644
--- a/nova/tests/api/ec2/test_cloud.py
+++ b/nova/tests/api/ec2/test_cloud.py
@@ -917,7 +917,7 @@ class CloudTestCase(test.TestCase):
         result = self.cloud.describe_instances(self.context)
         self.assertEqual(len(result['reservationSet']), 2)
 
-    def _block_device_mapping_create(self, instance_id, mappings):
+    def _block_device_mapping_create(self, instance_uuid, mappings):
         volumes = []
         for bdm in mappings:
             db.block_device_mapping_create(self.context, bdm)
@@ -931,7 +931,7 @@ class CloudTestCase(test.TestCase):
                         values[vol_key] = bdm[bdm_key]
                 vol = db.volume_create(self.context, values)
                 db.volume_attached(self.context, vol['id'],
-                                   instance_id, bdm['device_name'])
+                                   instance_uuid, bdm['device_name'])
                 volumes.append(vol)
         return volumes
 
@@ -987,7 +987,7 @@ class CloudTestCase(test.TestCase):
              'device_name': '/dev/sdb9',
              'virtual_name': 'ephemeral3'}]
 
-        volumes = self._block_device_mapping_create(instance_id, mappings0)
+        volumes = self._block_device_mapping_create(instance_uuid, mappings0)
         return (inst1, inst2, volumes)
 
     def _tearDownBlockDeviceMapping(self, inst1, inst2, volumes):
@@ -1910,14 +1910,14 @@ class CloudTestCase(test.TestCase):
             kwargs['id'] = volume_id
         return db.volume_create(self.context, kwargs)
 
-    def _assert_volume_attached(self, vol, instance_id, mountpoint):
-        self.assertEqual(vol['instance_id'], instance_id)
+    def _assert_volume_attached(self, vol, instance_uuid, mountpoint):
+        self.assertEqual(vol['instance_uuid'], instance_uuid)
         self.assertEqual(vol['mountpoint'], mountpoint)
         self.assertEqual(vol['status'], "in-use")
         self.assertEqual(vol['attach_status'], "attached")
 
     def _assert_volume_detached(self, vol):
-        self.assertEqual(vol['instance_id'], None)
+        self.assertEqual(vol['instance_uuid'], None)
         self.assertEqual(vol['mountpoint'], None)
         self.assertEqual(vol['status'], "available")
         self.assertEqual(vol['attach_status'], "detached")
@@ -1941,18 +1941,20 @@ class CloudTestCase(test.TestCase):
                                             'delete_on_termination': True},
                                            ]}
         ec2_instance_id = self._run_instance(**kwargs)
+        instance_uuid = ec2utils.ec2_instance_id_to_uuid(self.context,
+                                                         ec2_instance_id)
         instance_id = ec2utils.ec2_id_to_id(ec2_instance_id)
 
-        vols = db.volume_get_all_by_instance(self.context, instance_id)
+        vols = db.volume_get_all_by_instance_uuid(self.context, instance_uuid)
         self.assertEqual(len(vols), 2)
         for vol in vols:
             self.assertTrue(vol['id'] == vol1['id'] or vol['id'] == vol2['id'])
 
         vol = db.volume_get(self.context, vol1['id'])
-        self._assert_volume_attached(vol, instance_id, '/dev/vdb')
+        self._assert_volume_attached(vol, instance_uuid, '/dev/vdb')
 
         vol = db.volume_get(self.context, vol2['id'])
-        self._assert_volume_attached(vol, instance_id, '/dev/vdc')
+        self._assert_volume_attached(vol, instance_uuid, '/dev/vdc')
 
         result = self.cloud.stop_instances(self.context, [ec2_instance_id])
         self.assertTrue(result)
@@ -1963,13 +1965,13 @@ class CloudTestCase(test.TestCase):
         self._assert_volume_detached(vol)
 
         self.cloud.start_instances(self.context, [ec2_instance_id])
-        vols = db.volume_get_all_by_instance(self.context, instance_id)
+        vols = db.volume_get_all_by_instance_uuid(self.context, instance_uuid)
         self.assertEqual(len(vols), 2)
         for vol in vols:
             self.assertTrue(vol['id'] == vol1['id'] or vol['id'] == vol2['id'])
             self.assertTrue(vol['mountpoint'] == '/dev/vdb' or
                             vol['mountpoint'] == '/dev/vdc')
-            self.assertEqual(vol['instance_id'], instance_id)
+            self.assertEqual(vol['instance_uuid'], instance_uuid)
             self.assertEqual(vol['status'], "in-use")
             self.assertEqual(vol['attach_status'], "attached")
 
@@ -2001,12 +2003,14 @@ class CloudTestCase(test.TestCase):
                                             'delete_on_termination': True}]}
         ec2_instance_id = self._run_instance(**kwargs)
         instance_id = ec2utils.ec2_id_to_id(ec2_instance_id)
+        instance_uuid = ec2utils.ec2_instance_id_to_uuid(self.context,
+                                                         ec2_instance_id)
 
-        vols = db.volume_get_all_by_instance(self.context, instance_id)
+        vols = db.volume_get_all_by_instance_uuid(self.context, instance_uuid)
         self.assertEqual(len(vols), 1)
         for vol in vols:
             self.assertEqual(vol['id'], vol1['id'])
-            self._assert_volume_attached(vol, instance_id, '/dev/vdb')
+            self._assert_volume_attached(vol, instance_uuid, '/dev/vdb')
 
         vol = db.volume_get(self.context, vol2['id'])
         self._assert_volume_detached(vol)
@@ -2017,7 +2021,7 @@ class CloudTestCase(test.TestCase):
                                              volume_id=vol2['id'],
                                              device='/dev/vdc')
         vol = db.volume_get(self.context, vol2['id'])
-        self._assert_volume_attached(vol, instance_id, '/dev/vdc')
+        self._assert_volume_attached(vol, instance_uuid, '/dev/vdc')
 
         self.cloud.compute_api.detach_volume(self.context,
                                              volume_id=vol1['id'])
@@ -2032,11 +2036,11 @@ class CloudTestCase(test.TestCase):
             self._assert_volume_detached(vol)
 
         self.cloud.start_instances(self.context, [ec2_instance_id])
-        vols = db.volume_get_all_by_instance(self.context, instance_id)
+        vols = db.volume_get_all_by_instance_uuid(self.context, instance_uuid)
         self.assertEqual(len(vols), 1)
         for vol in vols:
             self.assertEqual(vol['id'], vol2['id'])
-            self._assert_volume_attached(vol, instance_id, '/dev/vdc')
+            self._assert_volume_attached(vol, instance_uuid, '/dev/vdc')
 
         vol = db.volume_get(self.context, vol1['id'])
         self._assert_volume_detached(vol)
@@ -2077,8 +2081,10 @@ class CloudTestCase(test.TestCase):
                                             'delete_on_termination': True}]}
         ec2_instance_id = self._run_instance(**kwargs)
         instance_id = ec2utils.ec2_id_to_id(ec2_instance_id)
+        instance_uuid = ec2utils.ec2_instance_id_to_uuid(self.context,
+                                                         ec2_instance_id)
 
-        vols = db.volume_get_all_by_instance(self.context, instance_id)
+        vols = db.volume_get_all_by_instance_uuid(self.context, instance_uuid)
         self.assertEqual(len(vols), 2)
         vol1_id = None
         vol2_id = None
@@ -2093,7 +2099,7 @@ class CloudTestCase(test.TestCase):
             else:
                 self.fail()
 
-            self._assert_volume_attached(vol, instance_id, mountpoint)
+            self._assert_volume_attached(vol, instance_uuid, mountpoint)
 
         self.assertTrue(vol1_id)
         self.assertTrue(vol2_id)
diff --git a/nova/tests/api/openstack/fakes.py b/nova/tests/api/openstack/fakes.py
index 90ee86676..f06878362 100644
--- a/nova/tests/api/openstack/fakes.py
+++ b/nova/tests/api/openstack/fakes.py
@@ -592,7 +592,7 @@ def stub_volume(id, **kwargs):
         'host': 'fakehost',
         'size': 1,
         'availability_zone': 'fakeaz',
-        'instance': {'uuid': 'fakeuuid'},
+        'instance_uuid': 'fakeuuid',
         'mountpoint': '/',
         'status': 'fakestatus',
         'attach_status': 'attached',
@@ -611,7 +611,7 @@ def stub_volume(id, **kwargs):
 
 def stub_volume_create(self, context, size, name, description, snapshot,
                        **param):
-    vol = stub_volume(1)
+    vol = stub_volume('1')
     vol['size'] = size
     vol['display_name'] = name
     vol['display_description'] = description
@@ -640,4 +640,4 @@ def stub_volume_get_notfound(self, context, volume_id):
 
 
 def stub_volume_get_all(self, context, search_opts=None):
-    return [stub_volume_get(self, context, 1)]
+    return [stub_volume_get(self, context, '1')]
diff --git a/nova/tests/api/openstack/volume/test_volumes.py b/nova/tests/api/openstack/volume/test_volumes.py
index 7befe9606..2b96d15a3 100644
--- a/nova/tests/api/openstack/volume/test_volumes.py
+++ b/nova/tests/api/openstack/volume/test_volumes.py
@@ -90,6 +90,7 @@ class VolumeApiTest(test.TestCase):
                                  'created_at': datetime.datetime(1, 1, 1,
                                                                 1, 1, 1),
                                  'size': 1}]}
+        self.maxDiff = None
         self.assertEqual(res_dict, expected)
 
     def test_volume_list_detail(self):
@@ -114,7 +115,7 @@ class VolumeApiTest(test.TestCase):
 
     def test_volume_show(self):
         req = fakes.HTTPRequest.blank('/v1/volumes/1')
-        res_dict = self.controller.show(req, 1)
+        res_dict = self.controller.show(req, '1')
         expected = {'volume': {'status': 'fakestatus',
                                'display_description': 'displaydesc',
                                'availability_zone': 'fakeaz',
@@ -139,7 +140,7 @@ class VolumeApiTest(test.TestCase):
         self.stubs.Set(volume_api.API, 'get', stub_volume_get)
 
         req = fakes.HTTPRequest.blank('/v1/volumes/1')
-        res_dict = self.controller.show(req, 1)
+        res_dict = self.controller.show(req, '1')
         expected = {'volume': {'status': 'fakestatus',
                                'display_description': 'displaydesc',
                                'availability_zone': 'fakeaz',
diff --git a/nova/tests/scheduler/test_scheduler.py b/nova/tests/scheduler/test_scheduler.py
index 0b3c0e06a..a662d6930 100644
--- a/nova/tests/scheduler/test_scheduler.py
+++ b/nova/tests/scheduler/test_scheduler.py
@@ -477,7 +477,6 @@ class SchedulerTestCase(test.TestCase):
         instance = self._live_migration_instance()
         db.instance_get(self.context, instance['id']).AndReturn(instance)
 
-        # Source checks (volume and source compute are up)
         db.service_get_all_compute_by_host(self.context,
                 instance['host']).AndReturn(['fake_service2'])
         utils.service_is_up('fake_service2').AndReturn(True)
diff --git a/nova/tests/test_libvirt.py b/nova/tests/test_libvirt.py
index 2391ea1ea..9e53df279 100644
--- a/nova/tests/test_libvirt.py
+++ b/nova/tests/test_libvirt.py
@@ -1215,7 +1215,9 @@ class LibvirtConnTestCase(test.TestCase):
                                           instance_dict)
         vol_dict = {'status': 'migrating', 'size': 1}
         volume_ref = db.volume_create(self.context, vol_dict)
-        db.volume_attached(self.context, volume_ref['id'], instance_ref['id'],
+        db.volume_attached(self.context,
+                           volume_ref['id'],
+                           instance_ref['uuid'],
                            '/dev/fake')
 
         # Preparing mocks
diff --git a/nova/tests/test_volume.py b/nova/tests/test_volume.py
index 27969ee5b..d979c3d0e 100644
--- a/nova/tests/test_volume.py
+++ b/nova/tests/test_volume.py
@@ -48,7 +48,9 @@ class VolumeTestCase(test.TestCase):
         self.flags(connection_type='fake')
         self.volume = importutils.import_object(FLAGS.volume_manager)
         self.context = context.get_admin_context()
-        self.instance_id = db.instance_create(self.context, {})['id']
+        instance = db.instance_create(self.context, {})
+        self.instance_id = instance['id']
+        self.instance_uuid = instance['uuid']
 
     def tearDown(self):
         db.instance_destroy(self.context, self.instance_id)
@@ -175,25 +177,26 @@ class VolumeTestCase(test.TestCase):
         inst['project_id'] = 'fake'
         inst['instance_type_id'] = '2'  # m1.tiny
         inst['ami_launch_index'] = 0
-        instance_id = db.instance_create(self.context, inst)['id']
+        instance = db.instance_create(self.context, {})
+        instance_id = instance['id']
+        instance_uuid = instance['uuid']
         mountpoint = "/dev/sdf"
         volume = self._create_volume()
         volume_id = volume['id']
         self.volume.create_volume(self.context, volume_id)
         if FLAGS.fake_tests:
-            db.volume_attached(self.context, volume_id, instance_id,
+            db.volume_attached(self.context, volume_id, instance_uuid,
                                mountpoint)
         else:
             self.compute.attach_volume(self.context,
-                                       instance_id,
+                                       instance_uuid,
                                        volume_id,
                                        mountpoint)
         vol = db.volume_get(context.get_admin_context(), volume_id)
         self.assertEqual(vol['status'], "in-use")
         self.assertEqual(vol['attach_status'], "attached")
         self.assertEqual(vol['mountpoint'], mountpoint)
-        instance_ref = db.volume_get_instance(self.context, volume_id)
-        self.assertEqual(instance_ref['id'], instance_id)
+        self.assertEqual(vol['instance_uuid'], instance_uuid)
 
         self.assertRaises(exception.NovaException,
                           self.volume.delete_volume,
@@ -203,7 +206,7 @@ class VolumeTestCase(test.TestCase):
             db.volume_detached(self.context, volume_id)
         else:
             self.compute.detach_volume(self.context,
-                                       instance_id,
+                                       instance_uuid,
                                        volume_id)
         vol = db.volume_get(self.context, volume_id)
         self.assertEqual(vol['status'], "available")
@@ -323,7 +326,7 @@ class VolumeTestCase(test.TestCase):
 
         volume = self._create_volume()
         self.volume.create_volume(self.context, volume['id'])
-        db.volume_attached(self.context, volume['id'], self.instance_id,
+        db.volume_attached(self.context, volume['id'], self.instance_uuid,
                            '/dev/sda1')
 
         volume_api = nova.volume.api.API()
@@ -383,7 +386,9 @@ class DriverTestCase(test.TestCase):
         log.logger.addHandler(logging.logging.StreamHandler(self.stream))
 
         inst = {}
-        self.instance_id = db.instance_create(self.context, inst)['id']
+        instance = db.instance_create(self.context, {})
+        self.instance_id = instance['id']
+        self.instance_uuid = instance['uuid']
 
     def _attach_volume(self):
         """Attach volumes to an instance. This function also sets
@@ -436,7 +441,7 @@ class ISCSITestCase(DriverTestCase):
 
             # each volume has a different mountpoint
             mountpoint = "/dev/sd" + chr((ord('b') + index))
-            db.volume_attached(self.context, vol_ref['id'], self.instance_id,
+            db.volume_attached(self.context, vol_ref['id'], self.instance_uuid,
                                mountpoint)
             volume_id_list.append(vol_ref['id'])
 
diff --git a/nova/volume/api.py b/nova/volume/api.py
index f62d41ea6..33643954c 100644
--- a/nova/volume/api.py
+++ b/nova/volume/api.py
@@ -248,13 +248,13 @@ class API(base.Base):
             self.update(context, volume, {"status": "available"})
 
     @wrap_check_policy
-    def attach(self, context, volume, instance_id, mountpoint):
+    def attach(self, context, volume, instance_uuid, mountpoint):
         host = volume['host']
         queue = self.db.queue_get_for(context, FLAGS.volume_topic, host)
         return rpc.call(context, queue,
                         {"method": "attach_volume",
                          "args": {"volume_id": volume['id'],
-                                  "instance_id": instance_id,
+                                  "instance_uuid": instance_uuid,
                                   "mountpoint": mountpoint}})
 
     @wrap_check_policy
diff --git a/nova/volume/manager.py b/nova/volume/manager.py
index bd03234d7..828451f7c 100644
--- a/nova/volume/manager.py
+++ b/nova/volume/manager.py
@@ -229,12 +229,15 @@ class VolumeManager(manager.SchedulerDependentManager):
         LOG.debug(_("snapshot %s: deleted successfully"), snapshot_ref['name'])
         return True
 
-    def attach_volume(self, context, volume_id, instance_id, mountpoint):
+    def attach_volume(self, context, volume_id, instance_uuid, mountpoint):
         """Updates db to show volume is attached"""
         # TODO(vish): refactor this into a more general "reserve"
+        if not utils.is_uuid_like(instance_uuid):
+            raise exception.InvalidUUID(instance_uuid)
+
         self.db.volume_attached(context,
                                 volume_id,
-                                instance_id,
+                                instance_uuid,
                                 mountpoint)
 
     def detach_volume(self, context, volume_id):
@@ -293,7 +296,10 @@ class VolumeManager(manager.SchedulerDependentManager):
     def check_for_export(self, context, instance_id):
         """Make sure whether volume is exported."""
         instance_ref = self.db.instance_get(context, instance_id)
-        for volume in instance_ref['volumes']:
+        volumes = self.db.volume_get_all_by_instance_uuid(context,
+                                                          instance_ref['uuid'])
+
+        for volume in volumes:
             self.driver.check_for_export(context, volume['id'])
 
     def _volume_stats_changed(self, stat1, stat2):