diff --git a/nailgun/nailgun/api/handlers/base.py b/nailgun/nailgun/api/handlers/base.py
index fd3c54e419..a3a25aeea2 100644
--- a/nailgun/nailgun/api/handlers/base.py
+++ b/nailgun/nailgun/api/handlers/base.py
@@ -165,15 +165,21 @@ class BaseHandler(object):
         ) as exc:
             notifier.notify("error", exc.message)
             raise self.http(400, exc.message)
+        except (
+            errors.NotAllowed,
+        ) as exc:
+            raise self.http(403, exc.message)
         except (
             errors.AlreadyExists
         ) as exc:
             raise self.http(409, exc.message)
         except (
             errors.InvalidData,
-            Exception
+            errors.NodeOffline,
         ) as exc:
-            raise self.http(400, str(exc))
+            raise self.http(400, exc.message)
+        except Exception as exc:
+            raise
         return valid_data
 
     def get_object_or_404(self, model, *args, **kwargs):
@@ -242,20 +248,10 @@ class SingleHandler(BaseHandler):
             obj_id
         )
 
-        try:
-            data = self.checked_data(
-                self.validator.validate_update,
-                instance=obj
-            )
-        except (
-            errors.InvalidData,
-            errors.NodeOffline
-        ) as exc:
-            raise self.http(400, exc.message)
-        except (
-            errors.AlreadyExists,
-        ) as exc:
-            raise self.http(409, exc.message)
+        data = self.checked_data(
+            self.validator.validate_update,
+            instance=obj
+        )
 
         self.single.update(obj, data)
         return self.single.to_json(obj)
@@ -283,13 +279,15 @@ class CollectionHandler(BaseHandler):
 
     validator = BasicValidator
     collection = None
+    eager = ()
 
     @content_json
     def GET(self):
         """:returns: Collection of JSONized REST objects.
         :http: * 200 (OK)
         """
-        return self.collection.to_json()
+        q = self.collection.eager(self.eager, None)
+        return self.collection.to_json(q)
 
     @content_json
     def POST(self):
@@ -298,6 +296,7 @@ class CollectionHandler(BaseHandler):
                * 400 (invalid object data specified)
                * 409 (object with such parameters already exists)
         """
+
         data = self.checked_data()
 
         try:
diff --git a/nailgun/nailgun/api/handlers/node.py b/nailgun/nailgun/api/handlers/node.py
index 9e13081e5b..6f60ccfbae 100644
--- a/nailgun/nailgun/api/handlers/node.py
+++ b/nailgun/nailgun/api/handlers/node.py
@@ -19,15 +19,14 @@ Handlers dealing with nodes
 """
 
 from datetime import datetime
-import json
 import traceback
 
-from sqlalchemy.orm import joinedload
-
 import web
 
 from nailgun.api.handlers.base import BaseHandler
+from nailgun.api.handlers.base import CollectionHandler
 from nailgun.api.handlers.base import content_json
+from nailgun.api.handlers.base import SingleHandler
 from nailgun.api.serializers.node import NodeInterfacesSerializer
 from nailgun.api.validators.network import NetAssignmentValidator
 from nailgun.api.validators.node import NodeValidator
@@ -45,117 +44,13 @@ from nailgun.network.manager import NetworkManager
 from nailgun import notifier
 
 
-class NodeHandler(BaseHandler):
-    fields = ('id', 'name', 'meta', 'progress', 'roles', 'pending_roles',
-              'status', 'mac', 'fqdn', 'ip', 'manufacturer', 'platform_name',
-              'pending_addition', 'pending_deletion', 'os_platform',
-              'error_type', 'online', 'cluster', 'uuid')
-    model = Node
+class NodeHandler(SingleHandler):
+
+    single = objects.Node
     validator = NodeValidator
 
-    @classmethod
-    def render(cls, instance, fields=None):
-        json_data = None
-        try:
-            json_data = BaseHandler.render(instance, fields=cls.fields)
-            json_data['network_data'] = NetworkManager.get_node_networks(
-                instance.id)
-        except Exception:
-            logger.error(traceback.format_exc())
-        return json_data
 
-    @content_json
-    def GET(self, node_id):
-        """:returns: JSONized Node object.
-        :http: * 200 (OK)
-               * 404 (node not found in db)
-        """
-        node = self.get_object_or_404(Node, node_id)
-        return self.render(node)
-
-    @content_json
-    def PUT(self, node_id):
-        """:returns: JSONized Node object.
-        :http: * 200 (OK)
-               * 400 (invalid node data specified)
-               * 404 (node not found in db)
-        """
-        node = self.get_object_or_404(Node, node_id)
-        if not node.attributes:
-            node.attributes = NodeAttributes(node_id=node.id)
-
-        data = self.checked_data(self.validator.validate_update)
-
-        network_manager = NetworkManager
-
-        old_cluster_id = node.cluster_id
-
-        if data.get("pending_roles") == [] and node.cluster:
-            objects.Cluster.clear_pending_changes(
-                node.cluster,
-                node_id=node.id
-            )
-
-        if "cluster_id" in data:
-            if data["cluster_id"] is None and node.cluster:
-                objects.Cluster.clear_pending_changes(
-                    node.cluster,
-                    node_id=node.id
-                )
-                node.roles = node.pending_roles = []
-                node.reset_name_to_default()
-            node.cluster_id = data["cluster_id"]
-            if node.cluster_id != old_cluster_id:
-                if old_cluster_id:
-                    network_manager.clear_assigned_networks(node)
-                if node.cluster_id:
-                    network_manager = node.cluster.network_manager
-                    network_manager.assign_networks_by_default(node)
-
-        regenerate_volumes = any((
-            'roles' in data and set(data['roles']) != set(node.roles),
-            'pending_roles' in data and
-            set(data['pending_roles']) != set(node.pending_roles),
-            node.cluster_id != old_cluster_id
-        ))
-
-        for key, value in data.iteritems():
-            # we don't allow to update id explicitly
-            # and updated cluster_id before all other fields
-            if key in ("id", "cluster_id"):
-                continue
-            setattr(node, key, value)
-        db().flush()
-
-        if not node.status in ('provisioning', 'deploying'
-                               ) and regenerate_volumes:
-            try:
-                node.attributes.volumes = \
-                    node.volume_manager.gen_volumes_info()
-            except Exception as exc:
-                msg = (
-                    u"Failed to generate volumes "
-                    "info for node '{0}': '{1}'"
-                ).format(
-                    node.name or data.get("mac") or data.get("id"),
-                    str(exc) or "see logs for details"
-                )
-                logger.warning(traceback.format_exc())
-                notifier.notify("error", msg, node_id=node.id)
-        return self.render(node)
-
-    def DELETE(self, node_id):
-        """:returns: Empty string
-        :http: * 204 (node successfully deleted)
-               * 404 (cluster not found in db)
-        """
-        node = self.get_object_or_404(Node, node_id)
-        db().delete(node)
-
-        raise self.http(204)
-
-
-class NodeCollectionHandler(BaseHandler):
+class NodeCollectionHandler(CollectionHandler):
     """Node collection handler
     """
 
@@ -165,25 +60,16 @@ class NodeCollectionHandler(BaseHandler):
               'error_type', 'online', 'cluster', 'uuid')
 
     validator = NodeValidator
-
-    @classmethod
-    def render(cls, nodes, fields=None):
-        json_list = []
-        network_manager = NetworkManager
-        ips_mapped = network_manager.get_grouped_ips_by_node()
-        networks_grouped = network_manager.get_networks_grouped_by_cluster()
-        for node in nodes:
-            try:
-                json_data = BaseHandler.render(node, fields=cls.fields)
-
-                json_data['network_data'] = network_manager.\
-                    get_node_networks_optimized(
-                        node, ips_mapped.get(node.id, []),
-                        networks_grouped.get(node.cluster_id, []))
-                json_list.append(json_data)
-            except Exception:
-                logger.error(traceback.format_exc())
-        return json_list
+    collection = objects.NodeCollection
+    eager = (
+        'cluster',
+        'nic_interfaces',
+        'nic_interfaces.assigned_networks_list',
+        'bond_interfaces',
+        'bond_interfaces.assigned_networks_list',
+        'role_list',
+        'pending_role_list'
+    )
 
     @content_json
     def GET(self):
@@ -194,133 +80,14 @@ class NodeCollectionHandler(BaseHandler):
         :http: * 200 (OK)
         """
         cluster_id = web.input(cluster_id=None).cluster_id
-        nodes = db().query(Node).options(
-            joinedload('cluster'),
-            joinedload('nic_interfaces'),
-            joinedload('nic_interfaces.assigned_networks_list'),
-            joinedload('bond_interfaces'),
-            joinedload('bond_interfaces.assigned_networks_list'),
-            joinedload('role_list'),
-            joinedload('pending_role_list'))
+        nodes = self.collection.eager(None, self.eager)
+
         if cluster_id == '':
-            nodes = nodes.filter_by(
-                cluster_id=None).all()
+            nodes = nodes.filter_by(cluster_id=None)
         elif cluster_id:
-            nodes = nodes.filter_by(
-                cluster_id=cluster_id).all()
-        else:
-            nodes = nodes.all()
-        return self.render(nodes)
+            nodes = nodes.filter_by(cluster_id=cluster_id)
 
-    @content_json
-    def POST(self):
-        """:returns: JSONized Node object.
-        :http: * 201 (cluster successfully created)
-               * 400 (invalid node data specified)
-               * 403 (node has incorrect status)
-               * 409 (node with such parameters already exists)
-        """
-        data = self.checked_data()
-        if data.get("status", "") != "discover":
-            msg = u"Node with mac '{0}' was not created, " \
-                  u"because request status is '{1}'."\
-                .format(data[u'mac'], data.get(u'status'))
-            logger.warning(msg)
-            raise self.http(
-                403, "Only bootstrap nodes are allowed to be registered."
-            )
-
-        node = Node(
-            #always produce unified (i.e. with lowercased letters)
-            #default name for nodes
-            name="Untitled ({0})".format(data['mac'][-5:].lower()),
-            timestamp=datetime.now()
-        )
-        if "cluster_id" in data:
-            # FIXME(vk): this part is needed only for tests. Normally,
-            # nodes are created only by agent and POST requests don't contain
-            # cluster_id, but our integration and unit tests widely use it.
-            # We need to assign cluster first
-            cluster_id = data.pop("cluster_id")
-            if cluster_id:
-                node.cluster = objects.Cluster.get_by_uid(cluster_id)
-        for key, value in data.iteritems():
-            if key == "id":
-                continue
-            elif key == "meta":
-                node.create_meta(value)
-            else:
-                setattr(node, key, value)
-
-        db().add(node)
-        db().flush()
-
-        node.attributes = NodeAttributes()
-
-        try:
-            node.attributes.volumes = node.volume_manager.gen_volumes_info()
-            if node.cluster:
-                objects.Cluster.add_pending_changes(
-                    node.cluster,
-                    "disks",
-                    node_id=node.id
-                )
-        except Exception as exc:
-            msg = (
-                u"Failed to generate volumes "
-                "info for node '{0}': '{1}'"
-            ).format(
-                node.name or data.get("mac") or data.get("id"),
-                str(exc) or "see logs for details"
-            )
-            logger.warning(traceback.format_exc())
-            notifier.notify("error", msg, node_id=node.id)
-        db().add(node)
-        db().flush()
-
-        network_manager = NetworkManager
-        # Add interfaces for node from 'meta'.
-        if node.meta and node.meta.get('interfaces'):
-            network_manager.update_interfaces_info(node)
-
-        if node.cluster_id:
-            network_manager = node.cluster.network_manager
-            network_manager.assign_networks_by_default(node)
-
-        try:
-            # we use multiplier of 1024 because there are no problems here
-            # with unfair size calculation
-            ram = str(round(float(
-                node.meta['memory']['total']) / 1073741824, 1)) + " GB RAM"
-        except Exception as exc:
-            logger.warning(traceback.format_exc())
-            ram = "unknown RAM"
-
-        try:
-            # we use multiplier of 1000 because disk vendors specify HDD size
-            # in terms of decimal capacity. Sources:
-            # http://knowledge.seagate.com/articles/en_US/FAQ/172191en
-            # http://physics.nist.gov/cuu/Units/binary.html
-            hd_size = round(float(
-                sum([d["size"] for d in node.meta["disks"]]) / 1000000000), 1)
-            # if HDD > 100 GB we show it's size in TB
-            if hd_size > 100:
-                hd_size = str(hd_size / 1000) + " TB HDD"
-            else:
-                hd_size = str(hd_size) + " GB HDD"
-        except Exception as exc:
-            logger.warning(traceback.format_exc())
-            hd_size = "unknown HDD"
-
-        cores = str(node.meta.get('cpu', {}).get('total', "unknown"))
-        notifier.notify(
-            "discover",
-            "New node is discovered: %s CPUs / %s / %s " %
-            (cores, ram, hd_size),
-            node_id=node.id
-        )
-
-        raise self.http(201, json.dumps(NodeHandler.render(node), indent=4))
+        return self.collection.to_json(nodes)
 
     @content_json
     def PUT(self):
@@ -328,112 +95,42 @@ class NodeCollectionHandler(BaseHandler):
         :http: * 200 (nodes are successfully updated)
                * 400 (invalid nodes data specified)
         """
-        data = self.checked_data(self.validator.validate_collection_update)
+        data = self.checked_data(
+            self.validator.validate_collection_update
+        )
 
-        q = db().query(Node)
         nodes_updated = []
         for nd in data:
-            node = None
-            if nd.get("mac"):
-                node = q.filter_by(mac=nd["mac"]).first() \
-                    or self.validator.validate_existent_node_mac_update(nd)
-            else:
-                node = q.get(nd["id"])
-
-            old_cluster_id = node.cluster_id
-
-            if nd.get("pending_roles") == [] and node.cluster:
-                objects.Cluster.clear_pending_changes(
-                    node.cluster,
-                    node_id=node.id
-                )
-
-            if "cluster_id" in nd:
-                if nd["cluster_id"] is None and node.cluster:
-                    objects.Cluster.clear_pending_changes(
-                        node.cluster,
-                        node_id=node.id
+            node = self.collection.single.get_by_mac_or_uid(
+                mac=nd.get("mac"),
+                node_uid=nd.get("id")
+            )
+            if not node:
+                can_search_by_ifaces = all([
+                    nd.get("mac"),
+                    nd.get("meta"),
+                    nd["meta"].get("interfaces")
+                ])
+                if can_search_by_ifaces:
+                    node = self.collection.single.search_by_interfaces(
+                        nd["meta"]["interfaces"]
                     )
-                    node.roles = node.pending_roles = []
-                    node.reset_name_to_default()
-                node.cluster_id = nd["cluster_id"]
 
-            regenerate_volumes = any((
-                'roles' in nd and
-                set(nd['roles']) != set(node.roles),
-                'pending_roles' in nd and
-                set(nd['pending_roles']) != set(node.pending_roles),
-                node.cluster_id != old_cluster_id
-            ))
-
-            for key, value in nd.iteritems():
-                if key == "meta":
-                    node.update_meta(value)
-                # don't update node ID
-                elif key != "id":
-                    setattr(node, key, value)
-            db().flush()
-            db().refresh(node)
-            if not node.attributes:
-                node.attributes = NodeAttributes()
-                db().flush()
-            if not node.attributes.volumes:
-                node.attributes.volumes = \
-                    node.volume_manager.gen_volumes_info()
-                db().flush()
-            if not node.status in ('provisioning', 'deploying'):
-                variants = (
-                    "disks" in node.meta and
-                    len(node.meta["disks"]) != len(
-                        filter(
-                            lambda d: d["type"] == "disk",
-                            node.attributes.volumes
-                        )
-                    ),
-                    regenerate_volumes
+            if not node:
+                raise self.http(
+                    404,
+                    "Can't find node: {0}".format(nd)
                 )
-                if any(variants):
-                    try:
-                        node.attributes.volumes = \
-                            node.volume_manager.gen_volumes_info()
-                        if node.cluster:
-                            objects.Cluster.add_pending_changes(
-                                node.cluster,
-                                "disks",
-                                node_id=node.id
-                            )
-                    except Exception as exc:
-                        msg = (
-                            "Failed to generate volumes "
-                            "info for node '{0}': '{1}'"
-                        ).format(
-                            node.name or data.get("mac") or data.get("id"),
-                            str(exc) or "see logs for details"
-                        )
-                        logger.warning(traceback.format_exc())
-                        notifier.notify("error", msg, node_id=node.id)
-
-                db().flush()
-
-            network_manager = NetworkManager
 
+            self.collection.single.update(node, nd)
             nodes_updated.append(node.id)
-            if 'cluster_id' in nd and nd['cluster_id'] != old_cluster_id:
-                if old_cluster_id:
-                    network_manager.clear_assigned_networks(node)
-                if node.cluster:
-                    network_manager = node.cluster.network_manager
-                    network_manager.assign_networks_by_default(node)
 
         # we need eagerload everything that is used in render
-        nodes = db().query(Node).options(
-            joinedload('cluster'),
-            joinedload('nic_interfaces'),
-            joinedload('nic_interfaces.assigned_networks_list'),
-            joinedload('bond_interfaces'),
-            joinedload('bond_interfaces.assigned_networks_list')).\
-            filter(Node.id.in_(nodes_updated)).all()
-        return self.render(nodes)
+        nodes = self.collection.get_by_id_list(
+            self.collection.eager(None, self.eager),
+            nodes_updated
+        )
+        return self.collection.to_json(nodes)
 
 
 class NodeAgentHandler(BaseHandler):
diff --git a/nailgun/nailgun/api/serializers/node.py b/nailgun/nailgun/api/serializers/node.py
index 94fdc82733..bce873ff4e 100644
--- a/nailgun/nailgun/api/serializers/node.py
+++ b/nailgun/nailgun/api/serializers/node.py
@@ -19,6 +19,30 @@ from nailgun import consts
 from nailgun.api.serializers.base import BasicSerializer
 
 
+class NodeSerializer(BasicSerializer):
+
+    fields = (
+        'id',
+        'name',
+        'meta',
+        'progress',
+        'roles',
+        'pending_roles',
+        'status',
+        'mac',
+        'fqdn',
+        'ip',
+        'manufacturer',
+        'platform_name',
+        'pending_addition',
+        'pending_deletion',
+        'os_platform',
+        'error_type',
+        'online',
+        'cluster'
+    )
+
+
 class NodeInterfacesSerializer(BasicSerializer):
 
     nic_fields = (
diff --git a/nailgun/nailgun/api/urls/v1.py b/nailgun/nailgun/api/urls/v1.py
index 3a3871fc1f..9c0dc04097 100644
--- a/nailgun/nailgun/api/urls/v1.py
+++ b/nailgun/nailgun/api/urls/v1.py
@@ -139,7 +139,7 @@ urls = (
     NodeCollectionHandler,
     r'/nodes/agent/?$',
     NodeAgentHandler,
-    r'/nodes/(?P<node_id>\d+)/?$',
+    r'/nodes/(?P<obj_id>\d+)/?$',
     NodeHandler,
     r'/nodes/(?P<node_id>\d+)/disks/?$',
     NodeDisksHandler,
diff --git a/nailgun/nailgun/api/validators/cluster.py b/nailgun/nailgun/api/validators/cluster.py
index 19a1a4d67a..b39985d17e 100644
--- a/nailgun/nailgun/api/validators/cluster.py
+++ b/nailgun/nailgun/api/validators/cluster.py
@@ -25,7 +25,10 @@ class ClusterValidator(BasicValidator):
     def _validate_common(cls, data):
         d = cls.validate_json(data)
         if d.get("name"):
-            if ClusterCollection.filter_by(name=d["name"]).first():
+            if ClusterCollection.filter_by(
+                query=None,
+                name=d["name"]
+            ).first():
                 raise errors.AlreadyExists(
                     "Environment with this name already exists",
                     log_message=True
diff --git a/nailgun/nailgun/api/validators/node.py b/nailgun/nailgun/api/validators/node.py
index 10e8d04264..2ad9d59384 100644
--- a/nailgun/nailgun/api/validators/node.py
+++ b/nailgun/nailgun/api/validators/node.py
@@ -17,6 +17,10 @@ from nailgun.api.validators.base import BasicValidator
 from nailgun.api.validators.json_schema.disks import disks_simple_format_schema
 from nailgun.api.validators.json_schema.node import node_format_schema
 
+from nailgun import consts
+
+from nailgun import objects
+
 from nailgun.db import db
 from nailgun.db.sqlalchemy.models import Node
 from nailgun.db.sqlalchemy.models import NodeNICInterface
@@ -98,9 +102,15 @@ class MetaValidator(BasicValidator):
 class NodeValidator(BasicValidator):
     @classmethod
     def validate(cls, data):
+        # TODO(enchantner): rewrite validators to use Node object
         data = cls.validate_json(data)
         cls.validate_schema(data, node_format_schema)
 
+        if data.get("status", "") != "discover":
+            raise errors.NotAllowed(
+                "Only bootstrap nodes are allowed to be registered."
+            )
+
         if 'mac' not in data:
             raise errors.InvalidData(
                 "No mac address specified",
@@ -173,20 +183,66 @@ class NodeValidator(BasicValidator):
                 )
 
     @classmethod
-    def validate_update(cls, data):
-        d = cls.validate_json(data)
-        if "status" in d and d["status"] not in Node.NODE_STATUSES:
+    def validate_update(cls, data, instance=None):
+        if isinstance(data, (str, unicode)):
+            d = cls.validate_json(data)
+        else:
+            d = data
+
+        if "status" in d and d["status"] not in consts.NODE_STATUSES:
             raise errors.InvalidData(
                 "Invalid status for node",
                 log_message=True
             )
-        if 'roles' in d and 'id' in d:
-            node = db().query(Node).get(d['id'])
+
+        if not d.get("mac") and not d.get("id") and not instance:
+            raise errors.InvalidData(
+                "Neither MAC nor ID is specified",
+                log_message=True
+            )
+
+        q = db().query(Node)
+        if "mac" in d:
+            if not d["mac"]:
+                raise errors.InvalidData(
+                    "Null MAC is specified",
+                    log_message=True
+                )
+            else:
+                existent_node = q.filter_by(mac=d["mac"]).first() \
+                    or cls.validate_existent_node_mac_update(d)
+                if not existent_node:
+                    raise errors.InvalidData(
+                        "Invalid MAC is specified",
+                        log_message=True
+                    )
+
+        if "id" in d and d["id"]:
+            existent_node = q.get(d["id"])
+            if not existent_node:
+                raise errors.InvalidData(
+                    "Invalid ID specified",
+                    log_message=True
+                )
+
+        if "roles" in d:
+            if instance:
+                node = instance
+            else:
+                node = objects.Node.get_by_mac_or_uid(
+                    mac=d.get("mac"),
+                    node_uid=d.get("id")
+                )
             cls.validate_roles(d, node)
+
         if 'meta' in d:
             d['meta'] = MetaValidator.validate_update(d['meta'])
         return d
 
+    @classmethod
+    def validate_delete(cls, instance):
+        pass
+
     @classmethod
     def validate_collection_update(cls, data):
         d = cls.validate_json(data)
@@ -196,38 +252,8 @@ class NodeValidator(BasicValidator):
                 log_message=True
             )
 
-        q = db().query(Node)
         for nd in d:
-            if not nd.get("mac") and not nd.get("id"):
-                raise errors.InvalidData(
-                    "Neither MAC nor ID is specified",
-                    log_message=True
-                )
-            if "mac" in nd and not nd["mac"]:
-                raise errors.InvalidData(
-                    "Null MAC is specified",
-                    log_message=True
-                )
-            else:
-                if nd.get("mac"):
-                    existent_node = q.filter_by(mac=nd["mac"]).first() \
-                        or cls.validate_existent_node_mac_update(nd)
-                    if not existent_node:
-                        raise errors.InvalidData(
-                            "Invalid MAC specified",
-                            log_message=True
-                        )
-                if nd.get("id"):
-                    existent_node = q.get(nd["id"])
-                    if not existent_node:
-                        raise errors.InvalidData(
-                            "Invalid ID specified",
-                            log_message=True
-                        )
-                if 'roles' in nd:
-                    cls.validate_roles(nd, existent_node)
-            if 'meta' in nd:
-                nd['meta'] = MetaValidator.validate_update(nd['meta'])
+            cls.validate_update(nd)
         return d
 
 
diff --git a/nailgun/nailgun/consts.py b/nailgun/nailgun/consts.py
index 4f6f3dfcfe..1f4a174b5b 100644
--- a/nailgun/nailgun/consts.py
+++ b/nailgun/nailgun/consts.py
@@ -71,6 +71,21 @@ CLUSTER_NET_SEGMENT_TYPES = Enum(
     'gre'
 )
 
+NODE_STATUSES = Enum(
+    'ready',
+    'discover',
+    'provisioning',
+    'provisioned',
+    'deploying',
+    'error'
+)
+
+NODE_ERRORS = Enum(
+    'deploy',
+    'provision',
+    'deletion'
+)
+
 NETWORK_INTERFACE_TYPES = Enum(
     'ether',
     'bond'
diff --git a/nailgun/nailgun/db/sqlalchemy/fixman.py b/nailgun/nailgun/db/sqlalchemy/fixman.py
index 8f180e90f5..ce1ab15433 100644
--- a/nailgun/nailgun/db/sqlalchemy/fixman.py
+++ b/nailgun/nailgun/db/sqlalchemy/fixman.py
@@ -30,7 +30,7 @@ import sqlalchemy.types
 from nailgun.db import db
 from nailgun.db.sqlalchemy import models
 from nailgun.logger import logger
-from nailgun.network.manager import NetworkManager
+from nailgun import objects
 from nailgun.settings import settings
 from nailgun.utils import dict_merge
 
@@ -178,11 +178,9 @@ def upload_fixture(fileobj, loader=None):
 
         # UGLY HACK for testing
         if new_obj.__class__.__name__ == 'Node':
-            new_obj.attributes = models.NodeAttributes()
-            db().commit()
-            new_obj.attributes.volumes = \
-                new_obj.volume_manager.gen_volumes_info()
-            NetworkManager.update_interfaces_info(new_obj)
+            objects.Node.create_attributes(new_obj)
+            objects.Node.update_volumes(new_obj)
+            objects.Node.update_interfaces(new_obj)
             db().commit()
 
 
diff --git a/nailgun/nailgun/db/sqlalchemy/models/node.py b/nailgun/nailgun/db/sqlalchemy/models/node.py
old mode 100644
new mode 100755
index c786f1b18c..fcee5448af
--- a/nailgun/nailgun/db/sqlalchemy/models/node.py
+++ b/nailgun/nailgun/db/sqlalchemy/models/node.py
@@ -68,28 +68,15 @@ class Role(Base):
 
 class Node(Base):
     __tablename__ = 'nodes'
-    NODE_STATUSES = (
-        'ready',
-        'discover',
-        'provisioning',
-        'provisioned',
-        'deploying',
-        'error'
-    )
-    NODE_ERRORS = (
-        'deploy',
-        'provision',
-        'deletion'
-    )
     id = Column(Integer, primary_key=True)
     uuid = Column(String(36), nullable=False,
                   default=lambda: str(uuid.uuid4()), unique=True)
     cluster_id = Column(Integer, ForeignKey('clusters.id'))
     name = Column(Unicode(100))
     status = Column(
-        Enum(*NODE_STATUSES, name='node_status'),
+        Enum(*consts.NODE_STATUSES, name='node_status'),
         nullable=False,
-        default='discover'
+        default=consts.NODE_STATUSES.discover
     )
     meta = Column(JSON, default={})
     mac = Column(LowercaseString(17), nullable=False, unique=True)
@@ -102,7 +89,7 @@ class Node(Base):
     pending_addition = Column(Boolean, default=False)
     pending_deletion = Column(Boolean, default=False)
     changes = relationship("ClusterChanges", backref="node")
-    error_type = Column(Enum(*NODE_ERRORS, name='node_error_type'))
+    error_type = Column(Enum(*consts.NODE_ERRORS, name='node_error_type'))
     error_msg = Column(String(255))
     timestamp = Column(DateTime, nullable=False)
     online = Column(Boolean, default=True)
@@ -256,16 +243,17 @@ class Node(Base):
     def update_meta(self, data):
         # helper for basic checking meta before updation
         result = []
-        for iface in data["interfaces"]:
-            if not self._check_interface_has_required_params(iface):
-                logger.warning(
-                    "Invalid interface data: {0}. "
-                    "Interfaces are not updated.".format(iface)
-                )
-                data["interfaces"] = self.meta.get("interfaces")
-                self.meta = data
-                return
-            result.append(self._clean_iface(iface))
+        if "interfaces" in data:
+            for iface in data["interfaces"]:
+                if not self._check_interface_has_required_params(iface):
+                    logger.warning(
+                        "Invalid interface data: {0}. "
+                        "Interfaces are not updated.".format(iface)
+                    )
+                    data["interfaces"] = self.meta.get("interfaces")
+                    self.meta = data
+                    return
+                result.append(self._clean_iface(iface))
 
         data["interfaces"] = result
         self.meta = data
@@ -273,14 +261,15 @@ class Node(Base):
     def create_meta(self, data):
         # helper for basic checking meta before creation
         result = []
-        for iface in data["interfaces"]:
-            if not self._check_interface_has_required_params(iface):
-                logger.warning(
-                    "Invalid interface data: {0}. "
-                    "Skipping interface.".format(iface)
-                )
-                continue
-            result.append(self._clean_iface(iface))
+        if "interfaces" in data:
+            for iface in data["interfaces"]:
+                if not self._check_interface_has_required_params(iface):
+                    logger.warning(
+                        "Invalid interface data: {0}. "
+                        "Skipping interface.".format(iface)
+                    )
+                    continue
+                result.append(self._clean_iface(iface))
 
         data["interfaces"] = result
         self.meta = data
diff --git a/nailgun/nailgun/errors/__init__.py b/nailgun/nailgun/errors/__init__.py
index d81c5ab2ef..c6e35ea3a5 100644
--- a/nailgun/nailgun/errors/__init__.py
+++ b/nailgun/nailgun/errors/__init__.py
@@ -25,6 +25,7 @@ default_messages = {
     # REST errors
     "CannotDelete": "Can't delete object",
     "CannotCreate": "Can't create object",
+    "NotAllowed": "Action is not allowed",
     "InvalidField": "Invalid field specified for object",
 
     # node discovering errors
diff --git a/nailgun/nailgun/network/manager.py b/nailgun/nailgun/network/manager.py
index 34745c4584..78f9a822c2 100644
--- a/nailgun/nailgun/network/manager.py
+++ b/nailgun/nailgun/network/manager.py
@@ -29,7 +29,7 @@ from netaddr import IPRange
 from sqlalchemy.orm import joinedload
 from sqlalchemy.sql import not_
 
-from nailgun import objects
+from nailgun.objects import Cluster
 
 from nailgun import consts
 from nailgun.db import db
@@ -243,7 +243,7 @@ class NetworkManager(object):
         :returns: None
         :raises: Exception
         """
-        cluster = objects.Cluster.get_by_uid(cluster_id)
+        cluster = Cluster.get_by_uid(cluster_id)
         if not cluster:
             raise Exception(u"Cluster id='%s' not found" % cluster_id)
 
@@ -362,6 +362,7 @@ class NetworkManager(object):
             ips = ips.filter_by(node=node_id)
         if network_id:
             ips = ips.filter_by(network=network_id)
+
         try:
             admin_net_id = cls.get_admin_network_group_id()
         except errors.AdminNetworkNotFound:
@@ -445,9 +446,13 @@ class NetworkManager(object):
             # Assign remaining networks to NIC #0
             # as all the networks must be assigned.
             # But network check will not pass if we get here.
-            logger.warn("Cannot assign all networks appropriately for"
-                        " node %r. Set all unassigned networks to the"
-                        " interface %r", node.name, nics[0]['name'])
+            logger.warn(
+                u"Cannot assign all networks appropriately for"
+                u"node %r. Set all unassigned networks to the"
+                u"interface %r",
+                node.name,
+                nics[0]['name']
+            )
             for ng_id in to_assign_ids:
                 nics[0].setdefault('assigned_networks', []).append(
                     {'id': ng_id, 'name': ngs_by_id[ng_id].name})
@@ -731,7 +736,9 @@ class NetworkManager(object):
         try:
             cls.__check_interfaces_correctness(node)
         except errors.InvalidInterfacesInfo as e:
-            logger.warn("Cannot update interfaces: %s" % str(e))
+            logger.warn(
+                "Cannot update interfaces: {0}".format(str(e))
+            )
             return
 
         for interface in node.meta["interfaces"]:
@@ -790,14 +797,14 @@ class NetworkManager(object):
         interface.node_id = node.id
         cls.__set_interface_attributes(interface, interface_attrs)
         db().add(interface)
-        db().commit()
-        node.nic_interfaces.append(interface)
+        db().flush()
 
     @classmethod
     def __update_existing_interface(cls, interface_id, interface_attrs):
         interface = db().query(NodeNICInterface).get(interface_id)
         cls.__set_interface_attributes(interface, interface_attrs)
-        db().commit()
+        db().add(interface)
+        db().flush()
 
     @classmethod
     def __set_interface_attributes(cls, interface, interface_attrs):
@@ -830,6 +837,7 @@ class NetworkManager(object):
                 mac_addresses, node_name))
 
             map(db().delete, interfaces_to_delete)
+        db().flush()
 
     @classmethod
     def get_admin_ip_for_node(cls, node):
@@ -887,7 +895,7 @@ class NetworkManager(object):
 
     @classmethod
     def get_end_point_ip(cls, cluster_id):
-        cluster_db = objects.Cluster.get_by_uid(cluster_id)
+        cluster_db = Cluster.get_by_uid(cluster_id)
         ip = None
         if cluster_db.is_ha_mode:
             ip = cls.assign_vip(cluster_db.id, "public")
@@ -988,7 +996,7 @@ class NetworkManager(object):
         :type  cluster_id: int
         :returns: None
         """
-        cluster_db = objects.Cluster.get_by_uid(cluster_id)
+        cluster_db = Cluster.get_by_uid(cluster_id)
         networks_metadata = cluster_db.release.networks_metadata
         networks_list = networks_metadata[cluster_db.net_provider]["networks"]
         used_nets = [IPNetwork(cls.get_admin_network_group().cidr)]
@@ -1078,7 +1086,7 @@ class NetworkManager(object):
                     cls.update_cidr_from_gw_mask(ng_db, ng)
                 if ng_db.meta.get("notation"):
                     cls.cleanup_network_group(ng_db)
-                objects.Cluster.add_pending_changes(ng_db.cluster, 'networks')
+                Cluster.add_pending_changes(ng_db.cluster, 'networks')
 
     @classmethod
     def cluster_has_bonds(cls, cluster_id):
diff --git a/nailgun/nailgun/objects/__init__.py b/nailgun/nailgun/objects/__init__.py
index 70cb3dcce4..e760e0e39a 100644
--- a/nailgun/nailgun/objects/__init__.py
+++ b/nailgun/nailgun/objects/__init__.py
@@ -24,5 +24,8 @@ from nailgun.objects.cluster import Attributes
 from nailgun.objects.cluster import Cluster
 from nailgun.objects.cluster import ClusterCollection
 
+from nailgun.objects.node import Node
+from nailgun.objects.node import NodeCollection
+
 from nailgun.objects.task import Task
 from nailgun.objects.task import TaskCollection
diff --git a/nailgun/nailgun/objects/base.py b/nailgun/nailgun/objects/base.py
index 6304350567..3f343616df 100644
--- a/nailgun/nailgun/objects/base.py
+++ b/nailgun/nailgun/objects/base.py
@@ -16,6 +16,8 @@
 
 import json
 
+from sqlalchemy.orm import joinedload
+
 from nailgun.api.serializers.base import BasicSerializer
 from nailgun.db import db
 from nailgun.errors import errors
@@ -93,7 +95,7 @@ class NailgunCollection(object):
         ).yield_per(yield_per)
 
     @classmethod
-    def filter_by(cls, yield_per=100, **kwargs):
+    def filter_by(cls, query, yield_per=100, **kwargs):
         for k in kwargs.iterkeys():
             if k not in cls.single.schema["properties"]:
                 raise AttributeError(
@@ -103,14 +105,25 @@ class NailgunCollection(object):
                     )
                 )
 
-        return db().query(
-            cls.single.model
-        ).filter_by(
-            **kwargs
-        ).yield_per(yield_per)
+        use_query = query or cls.all(yield_per=yield_per)
+        return use_query.filter_by(**kwargs)
 
     @classmethod
-    def to_list(cls, fields=None, yield_per=100, query=None):
+    def get_by_id_list(cls, query, id_list, yield_per=100):
+        use_query = query or cls.all(yield_per=yield_per)
+        return use_query.filter(cls.single.model.id.in_(id_list))
+
+    @classmethod
+    def eager(cls, query, fields, yield_per=100):
+        use_query = query or cls.all(yield_per=yield_per)
+        if fields:
+            return use_query.options(
+                *[joinedload(f) for f in fields]
+            )
+        return use_query
+
+    @classmethod
+    def to_list(cls, query=None, fields=None, yield_per=100):
         use_query = query or cls.all(yield_per=yield_per)
         return map(
             lambda o: cls.single.to_dict(o, fields=fields),
@@ -118,7 +131,7 @@ class NailgunCollection(object):
         )
 
     @classmethod
-    def to_json(cls, fields=None, yield_per=100, query=None):
+    def to_json(cls, query=None, fields=None, yield_per=100):
         return json.dumps(
             cls.to_list(
                 fields=fields,
diff --git a/nailgun/nailgun/objects/node.py b/nailgun/nailgun/objects/node.py
new file mode 100755
index 0000000000..434380c3d4
--- /dev/null
+++ b/nailgun/nailgun/objects/node.py
@@ -0,0 +1,386 @@
+# -*- coding: utf-8 -*-
+
+#    Copyright 2013 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.
+
+import traceback
+
+from datetime import datetime
+
+from nailgun import consts
+
+from nailgun.api.serializers.node import NodeSerializer
+
+from nailgun import notifier
+
+from nailgun.db import db
+from nailgun.db.sqlalchemy import models
+from nailgun.errors import errors
+from nailgun.logger import logger
+from nailgun.network.manager import NetworkManager
+
+from nailgun.objects import Cluster
+from nailgun.objects import NailgunCollection
+from nailgun.objects import NailgunObject
+
+
+class Node(NailgunObject):
+
+    model = models.Node
+    serializer = NodeSerializer
+
+    schema = {
+        "$schema": "http://json-schema.org/draft-04/schema#",
+        "title": "Node",
+        "description": "Serialized Node object",
+        "type": "object",
+        "properties": {
+            "id": {"type": "number"},
+            "cluster_id": {"type": "number"},
+            "name": {"type": "string"},
+            "status": {
+                "type": "string",
+                "enum": list(consts.NODE_STATUSES)
+            },
+            "meta": {"type": "object"},
+            "mac": {"type": "string"},
+            "api": {"type": "string"},
+            "fqdn": {"type": "string"},
+            "manufacturer": {"type": "string"},
+            "platform_name": {"type": "string"},
+            "progress": {"type": "number"},
+            "os_platform": {"type": "string"},
+            "pending_addition": {"type": "boolean"},
+            "pending_deletion": {"type": "boolean"},
+            "error_type": {
+                "type": "string",
+                "enum": list(consts.NODE_ERRORS)
+            },
+            "error_msg": {"type": "string"},
+            "online": {"type": "boolean"},
+            "roles": {"type": "array"},
+            "pending_roles": {"type": "array"},
+            "agent_checksum": {"type": "string"}
+        }
+    }
+
+    @classmethod
+    def get_by_mac_or_uid(cls, mac=None, node_uid=None):
+        node = None
+        if not mac and not node_uid:
+            return node
+
+        q = db().query(cls.model)
+        if mac:
+            node = q.filter_by(mac=mac).first()
+        else:
+            node = q.get(node_uid)
+        return node
+
+    @classmethod
+    def search_by_interfaces(cls, interfaces):
+        return db().query(cls.model).join(
+            models.NodeNICInterface,
+            cls.model.nic_interfaces
+        ).filter(
+            models.NodeNICInterface.mac.in_(
+                [n["mac"] for n in interfaces]
+            )
+        ).first()
+
+    @classmethod
+    def create(cls, data):
+        if "name" not in data:
+            data["name"] = "Untitled ({0})".format(
+                data['mac'][-5:].lower()
+            )
+        data["timestamp"] = datetime.now()
+        data.pop("id", None)
+
+        #TODO(enchantner): fix this temporary hack in clients
+        if "cluster_id" not in data and "cluster" in data:
+            cluster_id = data.pop("cluster", None)
+            data["cluster_id"] = cluster_id
+
+        roles = data.pop("roles", None)
+        pending_roles = data.pop("pending_roles", None)
+
+        new_node_meta = data.pop("meta", {})
+        new_node_cluster_id = data.pop("cluster_id", None)
+        new_node = super(Node, cls).create(data)
+        new_node.create_meta(new_node_meta)
+        db().flush()
+
+        # Add interfaces for node from 'meta'.
+        if new_node.meta and new_node.meta.get('interfaces'):
+            cls.update_interfaces(new_node)
+
+        # adding node into cluster
+        if new_node_cluster_id:
+            cls.add_into_cluster(new_node, new_node_cluster_id)
+
+        # updating roles
+        if roles is not None:
+            cls.update_roles(new_node, roles)
+        if pending_roles is not None:
+            cls.update_pending_roles(new_node, pending_roles)
+
+        # creating attributes
+        cls.create_attributes(new_node)
+        cls.update_volumes(new_node)
+
+        cls.create_discover_notification(new_node)
+        return new_node
+
+    @classmethod
+    def create_attributes(cls, instance):
+        new_attributes = models.NodeAttributes()
+        instance.attributes = new_attributes
+        db().add(new_attributes)
+        db().add(instance)
+        db().flush()
+        return new_attributes
+
+    @classmethod
+    def update_interfaces(cls, instance):
+        NetworkManager.update_interfaces_info(instance)
+
+    @classmethod
+    def update_volumes(cls, instance):
+        attrs = instance.attributes
+        if not attrs:
+            attrs = cls.create_attributes(instance)
+
+        try:
+            attrs.volumes = instance.volume_manager.gen_volumes_info()
+        except Exception as exc:
+            msg = (
+                u"Failed to generate volumes "
+                u"info for node '{0}': '{1}'"
+            ).format(
+                instance.name or instance.mac or instance.id,
+                str(exc) or "see logs for details"
+            )
+            logger.warning(traceback.format_exc())
+            notifier.notify("error", msg, node_id=instance.id)
+
+        if instance.cluster_id:
+            Cluster.add_pending_changes(
+                instance.cluster,
+                "disks",
+                node_id=instance.id
+            )
+
+        db().add(attrs)
+        db().flush()
+
+    @classmethod
+    def create_discover_notification(cls, instance):
+        try:
+            # we use multiplier of 1024 because there are no problems here
+            # with unfair size calculation
+            ram = str(round(float(
+                instance.meta['memory']['total']) / 1073741824, 1)) + " GB RAM"
+        except Exception:
+            logger.warning(traceback.format_exc())
+            ram = "unknown RAM"
+
+        try:
+            # we use multiplier of 1000 because disk vendors specify HDD size
+            # in terms of decimal capacity. Sources:
+            # http://knowledge.seagate.com/articles/en_US/FAQ/172191en
+            # http://physics.nist.gov/cuu/Units/binary.html
+            hd_size = round(
+                float(
+                    sum(
+                        [d["size"] for d in instance.meta["disks"]]
+                    ) / 1000000000
+                ),
+                1
+            )
+            # if HDD > 100 GB we show it's size in TB
+            if hd_size > 100:
+                hd_size = str(hd_size / 1000) + " TB HDD"
+            else:
+                hd_size = str(hd_size) + " GB HDD"
+        except Exception:
+            logger.warning(traceback.format_exc())
+            hd_size = "unknown HDD"
+
+        cores = str(instance.meta.get('cpu', {}).get('total', "unknown"))
+        notifier.notify(
+            "discover",
+            "New node is discovered: %s CPUs / %s / %s " %
+            (cores, ram, hd_size),
+            node_id=instance.id
+        )
+
+    @classmethod
+    def update(cls, instance, data):
+        data.pop("id", None)
+
+        roles = data.pop("roles", None)
+        pending_roles = data.pop("pending_roles", None)
+        new_meta = data.pop("meta", None)
+
+        #TODO(enchantner): fix this temporary hack in clients
+        if "cluster_id" not in data and "cluster" in data:
+            cluster_id = data.pop("cluster", None)
+            data["cluster_id"] = cluster_id
+
+        if new_meta:
+            instance.update_meta(new_meta)
+            # smarter check needed
+            cls.update_interfaces(instance)
+
+        new_cluster_id = instance.cluster_id
+        cluster_changed = False
+        if "cluster_id" in data:
+            new_cluster_id = data.pop("cluster_id")
+            if instance.cluster_id:
+                if new_cluster_id is None:
+                    # removing node from cluster
+                    cluster_changed = True
+                    cls.remove_from_cluster(instance)
+                elif new_cluster_id != instance.cluster_id:
+                    # changing node cluster to another
+                    # (is currently not allowed)
+                    raise errors.CannotUpdate(
+                        u"Changing cluster on the fly is not allowed"
+                    )
+            else:
+                if new_cluster_id is not None:
+                    # assigning node to cluster
+                    cluster_changed = True
+                    cls.add_into_cluster(instance, new_cluster_id)
+
+        # calculating flags
+        roles_changed = (
+            roles is not None and set(roles) != set(instance.roles)
+        )
+        pending_roles_changed = (
+            pending_roles is not None and
+            set(pending_roles) != set(instance.pending_roles)
+        )
+
+        super(Node, cls).update(instance, data)
+
+        if roles_changed:
+            cls.update_roles(instance, roles)
+        if pending_roles_changed:
+            cls.update_pending_roles(instance, pending_roles)
+
+        if any((
+            roles_changed,
+            pending_roles_changed,
+            cluster_changed
+        )) and instance.status not in (
+            consts.NODE_STATUSES.provisioning,
+            consts.NODE_STATUSES.deploying
+        ):
+            cls.update_volumes(instance)
+
+        return instance
+
+    @classmethod
+    def update_roles(cls, instance, new_roles):
+        if not instance.cluster_id:
+            logger.warning(
+                u"Attempting to assign roles to node "
+                u"'{0}' which isn't added to cluster".format(
+                    instance.name or instance.id
+                )
+            )
+            return
+
+        instance.role_list = db().query(models.Role).filter_by(
+            release_id=instance.cluster.release_id,
+        ).filter(
+            models.Role.name.in_(new_roles)
+        ).all()
+        db().flush()
+        db().refresh(instance)
+
+    @classmethod
+    def update_pending_roles(cls, instance, new_pending_roles):
+        if not instance.cluster_id:
+            logger.warning(
+                u"Attempting to assign pending roles to node "
+                u"'{0}' which isn't added to cluster".format(
+                    instance.name or instance.id
+                )
+            )
+            return
+
+        logger.debug(
+            u"Updating pending roles for node {0}: {1}".format(
+                instance.id,
+                new_pending_roles
+            )
+        )
+
+        if new_pending_roles == []:
+            instance.pending_role_list = []
+            # research why the hell we need this
+            Cluster.clear_pending_changes(
+                instance.cluster,
+                node_id=instance.id
+            )
+        else:
+            instance.pending_role_list = db().query(models.Role).filter_by(
+                release_id=instance.cluster.release_id,
+            ).filter(
+                models.Role.name.in_(new_pending_roles)
+            ).all()
+
+        db().flush()
+        db().refresh(instance)
+
+    @classmethod
+    def add_into_cluster(cls, instance, cluster_id):
+        instance.cluster_id = cluster_id
+        db().flush()
+        network_manager = instance.cluster.network_manager
+        network_manager.assign_networks_by_default(instance)
+
+    @classmethod
+    def remove_from_cluster(cls, instance):
+        Cluster.clear_pending_changes(
+            instance.cluster,
+            node_id=instance.id
+        )
+        instance.cluster_id = None
+        instance.roles = instance.pending_roles = []
+        instance.reset_name_to_default()
+        db().flush()
+        db().refresh(instance)
+        NetworkManager.clear_assigned_networks(instance)
+
+    @classmethod
+    def to_dict(cls, instance, fields=None):
+        node_dict = super(Node, cls).to_dict(instance, fields=fields)
+        ips_mapped = NetworkManager.get_grouped_ips_by_node()
+        networks_grouped = NetworkManager.get_networks_grouped_by_cluster()
+
+        node_dict['network_data'] = NetworkManager.get_node_networks_optimized(
+            instance,
+            ips_mapped.get(instance.id, []),
+            networks_grouped.get(instance.cluster_id, [])
+        )
+        return node_dict
+
+
+class NodeCollection(NailgunCollection):
+
+    single = Node
diff --git a/nailgun/nailgun/objects/task.py b/nailgun/nailgun/objects/task.py
index 3d77cd9785..1aa569a6de 100644
--- a/nailgun/nailgun/objects/task.py
+++ b/nailgun/nailgun/objects/task.py
@@ -77,5 +77,5 @@ class TaskCollection(NailgunCollection):
     @classmethod
     def get_by_cluster_id(cls, cluster_id):
         if cluster_id == '':
-            return cls.filter_by(cluster_id=None)
-        return cls.filter_by(cluster_id=cluster_id)
+            return cls.filter_by(None, cluster_id=None)
+        return cls.filter_by(None, cluster_id=cluster_id)
diff --git a/nailgun/nailgun/task/task.py b/nailgun/nailgun/task/task.py
index 605e09c9ea..8134e8570a 100644
--- a/nailgun/nailgun/task/task.py
+++ b/nailgun/nailgun/task/task.py
@@ -453,8 +453,10 @@ class CheckBeforeDeploymentTask(object):
                     node.volume_manager.check_disk_space_for_deployment()
         except errors.NotEnoughFreeSpace:
             raise errors.NotEnoughFreeSpace(
-                u"Node '%s' has insufficient disk space" %
-                node.human_readable_name)
+                u"Node '{0}' has insufficient disk space".format(
+                    node.human_readable_name
+                )
+            )
 
     @classmethod
     def _check_volumes(cls, task):
diff --git a/nailgun/nailgun/test/base.py b/nailgun/nailgun/test/base.py
index 3549895225..e3c657736d 100644
--- a/nailgun/nailgun/test/base.py
+++ b/nailgun/nailgun/test/base.py
@@ -46,7 +46,6 @@ from nailgun.logger import logger
 
 from nailgun.db.sqlalchemy.fixman import load_fixture
 from nailgun.db.sqlalchemy.fixman import upload_fixture
-from nailgun.db.sqlalchemy.models import Node
 from nailgun.db.sqlalchemy.models import NodeAttributes
 from nailgun.db.sqlalchemy.models import NodeNICInterface
 from nailgun.db.sqlalchemy.models import Notification
@@ -55,6 +54,7 @@ from nailgun.db.sqlalchemy.models import Task
 
 # here come objects
 from nailgun.objects import Cluster
+from nailgun.objects import Node
 from nailgun.objects import Release
 
 from nailgun.app import build_app
@@ -250,7 +250,7 @@ class Environment(object):
                 return None
             self.tester.assertEquals(resp.status_code, expect_http)
             node = json.loads(resp.body)
-            node_db = self.db.query(Node).get(node['id'])
+            node_db = Node.get_by_uid(node['id'])
             if 'interfaces' not in node_data['meta'] \
                     or not node_data['meta']['interfaces']:
                 self._set_interfaces_if_not_set_in_meta(
@@ -258,25 +258,8 @@ class Environment(object):
                     kwargs.get('meta', None))
             self.nodes.append(node_db)
         else:
-            node = Node()
-            node.timestamp = datetime.now()
-            if 'cluster_id' in node_data:
-                cluster_id = node_data.pop('cluster_id')
-                for cluster in self.clusters:
-                    if cluster.id == cluster_id:
-                        node.cluster = cluster
-                        break
-                else:
-                    node.cluster_id = cluster_id
-            for key, value in node_data.iteritems():
-                setattr(node, key, value)
-            node.attributes = self.create_attributes()
-            node.attributes.volumes = node.volume_manager.gen_volumes_info()
-            self.db.add(node)
-            self.db.commit()
-            if node.meta and node.meta.get('interfaces'):
-                self._create_interfaces_from_meta(node)
-
+            node = Node.create(node_data)
+            db().commit()
             self.nodes.append(node)
 
         return node
diff --git a/nailgun/nailgun/test/integration/test_changes_model.py b/nailgun/nailgun/test/integration/test_changes_model.py
index 2fd4cfc806..24489ff48c 100644
--- a/nailgun/nailgun/test/integration/test_changes_model.py
+++ b/nailgun/nailgun/test/integration/test_changes_model.py
@@ -190,8 +190,12 @@ class TestClusterChanges(BaseIntegrationTest):
             name="networks"
         ).all()
         self.assertEquals(len(networks_changes), 1)
+        disks_changes = self.db.query(ClusterChanges).filter_by(
+            name="disks"
+        ).all()
+        self.assertEquals(len(disks_changes), 1)
         all_changes = self.db.query(ClusterChanges).all()
-        self.assertEquals(len(all_changes), 2)
+        self.assertEquals(len(all_changes), 3)
 
     @fake_tasks(godmode=True)
     def test_role_unassignment_drops_changes(self):
@@ -209,7 +213,7 @@ class TestClusterChanges(BaseIntegrationTest):
         )
         self.app.put(
             reverse("NodeHandler",
-                    kwargs={"node_id": new_node["id"]}),
+                    kwargs={"obj_id": new_node["id"]}),
             json.dumps({
                 "cluster": None,
                 "pending_addition": False,
@@ -217,7 +221,6 @@ class TestClusterChanges(BaseIntegrationTest):
             }),
             headers=self.default_headers
         )
-
         all_changes = self.db.query(ClusterChanges).filter_by(
             cluster_id=self.env.clusters[0].id,
             node_id=new_node["id"]
diff --git a/nailgun/nailgun/test/integration/test_deployment_error_handling.py b/nailgun/nailgun/test/integration/test_deployment_error_handling.py
index 94b7a47a10..a1bca0978f 100644
--- a/nailgun/nailgun/test/integration/test_deployment_error_handling.py
+++ b/nailgun/nailgun/test/integration/test_deployment_error_handling.py
@@ -81,11 +81,11 @@ class TestErrors(BaseIntegrationTest):
         self.assertIsNotNone(
             self.db.query(Notification).filter_by(message=err_msg).first()
         )
-        self.assertEqual(
+        self.assertIsNotNone(
             self.db.query(Notification).filter_by(
-                node_id=self.env.nodes[2].id
-            ).first().message,
-            "Failed to deploy node 'Third': I forgot about teapot!"
+                node_id=self.env.nodes[2].id,
+                message="Failed to deploy node 'Third': I forgot about teapot!"
+            ).first()
         )
         self.env.refresh_nodes()
         self.env.refresh_clusters()
diff --git a/nailgun/nailgun/test/integration/test_node_collection_handlers.py b/nailgun/nailgun/test/integration/test_node_collection_handlers.py
index 32296c9274..fea4b78be7 100644
--- a/nailgun/nailgun/test/integration/test_node_collection_handlers.py
+++ b/nailgun/nailgun/test/integration/test_node_collection_handlers.py
@@ -207,14 +207,16 @@ class TestHandlers(BaseIntegrationTest):
             json.dumps([{'id': None,
                          'mac': node.mac,
                          'manufacturer': 'man5'}]),
-            headers=self.default_headers)
+            headers=self.default_headers
+        )
         self.assertEquals(resp.status_code, 200)
 
         resp = self.app.put(
             reverse('NodeCollectionHandler'),
             json.dumps([{'id': node.id,
                          'manufacturer': 'man6'}]),
-            headers=self.default_headers)
+            headers=self.default_headers
+        )
         self.assertEquals(resp.status_code, 200)
 
         resp = self.app.put(
@@ -335,7 +337,8 @@ class TestHandlers(BaseIntegrationTest):
         )
         node2_json = {
             "mac": self.env.generate_random_mac(),
-            "meta": self.env.default_metadata()
+            "meta": self.env.default_metadata(),
+            "status": "discover"
         }
         node2_json["meta"]["interfaces"][0]["mac"] = node1.mac
         resp = self.app.post(
@@ -424,7 +427,7 @@ class TestHandlers(BaseIntegrationTest):
         node = self.env.create_node(api=False)
         resp = self.app.post(
             reverse('NodeCollectionHandler'),
-            json.dumps({'mac': node.mac}),
+            json.dumps({'mac': node.mac, 'status': 'discover'}),
             headers=self.default_headers,
             expect_errors=True)
         self.assertEquals(409, resp.status_code)
@@ -485,7 +488,7 @@ class TestHandlers(BaseIntegrationTest):
         )[0]['id']
 
         self.app.delete(
-            reverse('NodeHandler', {'node_id': node_id})
+            reverse('NodeHandler', {'obj_id': node_id})
         )
 
         node_name_test(node_mac.lower())
diff --git a/nailgun/nailgun/test/integration/test_node_handler.py b/nailgun/nailgun/test/integration/test_node_handler.py
index e140768bf0..64d8847882 100644
--- a/nailgun/nailgun/test/integration/test_node_handler.py
+++ b/nailgun/nailgun/test/integration/test_node_handler.py
@@ -26,7 +26,7 @@ class TestHandlers(BaseIntegrationTest):
     def test_node_get(self):
         node = self.env.create_node(api=False)
         resp = self.app.get(
-            reverse('NodeHandler', kwargs={'node_id': node.id}),
+            reverse('NodeHandler', kwargs={'obj_id': node.id}),
             headers=self.default_headers)
         self.assertEquals(200, resp.status_code)
         response = json.loads(resp.body)
@@ -60,7 +60,7 @@ class TestHandlers(BaseIntegrationTest):
     def test_node_deletion(self):
         node = self.env.create_node(api=False)
         resp = self.app.delete(
-            reverse('NodeHandler', kwargs={'node_id': node.id}),
+            reverse('NodeHandler', kwargs={'obj_id': node.id}),
             "",
             headers=self.default_headers,
             expect_errors=True
@@ -71,7 +71,7 @@ class TestHandlers(BaseIntegrationTest):
         new_metadata = self.env.default_metadata()
         node = self.env.create_node(api=False)
         resp = self.app.put(
-            reverse('NodeHandler', kwargs={'node_id': node.id}),
+            reverse('NodeHandler', kwargs={'obj_id': node.id}),
             json.dumps({'meta': new_metadata}),
             headers=self.default_headers)
         self.assertEquals(resp.status_code, 200)
@@ -87,7 +87,7 @@ class TestHandlers(BaseIntegrationTest):
         node = self.env.create_node(api=False)
         params = {'status': 'error'}
         resp = self.app.put(
-            reverse('NodeHandler', kwargs={'node_id': node.id}),
+            reverse('NodeHandler', kwargs={'obj_id': node.id}),
             json.dumps(params),
             headers=self.default_headers)
         self.assertEquals(resp.status_code, 200)
@@ -97,7 +97,7 @@ class TestHandlers(BaseIntegrationTest):
         node = self.env.create_node(api=False)
         for flag in flags:
             resp = self.app.put(
-                reverse('NodeHandler', kwargs={'node_id': node.id}),
+                reverse('NodeHandler', kwargs={'obj_id': node.id}),
                 json.dumps({flag: True}),
                 headers=self.default_headers
             )
@@ -113,7 +113,7 @@ class TestHandlers(BaseIntegrationTest):
     def test_put_returns_400_if_no_body(self):
         node = self.env.create_node(api=False)
         resp = self.app.put(
-            reverse('NodeHandler', kwargs={'node_id': node.id}),
+            reverse('NodeHandler', kwargs={'obj_id': node.id}),
             "",
             headers=self.default_headers,
             expect_errors=True)
@@ -123,7 +123,7 @@ class TestHandlers(BaseIntegrationTest):
         node = self.env.create_node(api=False)
         params = {'status': 'invalid_status'}
         resp = self.app.put(
-            reverse('NodeHandler', kwargs={'node_id': node.id}),
+            reverse('NodeHandler', kwargs={'obj_id': node.id}),
             json.dumps(params),
             headers=self.default_headers,
             expect_errors=True)
diff --git a/nailgun/nailgun/test/integration/test_rpc_consumer.py b/nailgun/nailgun/test/integration/test_rpc_consumer.py
index d3e076c8b7..4e15780654 100644
--- a/nailgun/nailgun/test/integration/test_rpc_consumer.py
+++ b/nailgun/nailgun/test/integration/test_rpc_consumer.py
@@ -318,7 +318,7 @@ class TestVerifyNetworks(BaseIntegrationTest):
             u'absent_vlans': [100, 101, 102, 103, 104],
             u'interface': 'eth0',
             u'mac': node2.interfaces[0].mac,
-            u'name': None,
+            u'name': 'Untitled ({0})'.format(node2.mac[-5:].lower()),
             u'uid': node2.id}])
 
     def test_verify_networks_resp_forgotten_node_error(self):
diff --git a/nailgun/nailgun/test/unit/test_handlers.py b/nailgun/nailgun/test/unit/test_handlers.py
index 356d461d43..36c641d9f3 100644
--- a/nailgun/nailgun/test/unit/test_handlers.py
+++ b/nailgun/nailgun/test/unit/test_handlers.py
@@ -26,7 +26,7 @@ class TestHandlers(BaseIntegrationTest):
     def test_all_api_urls_404_or_405(self):
         urls = {
             'ClusterHandler': {'obj_id': 1},
-            'NodeHandler': {'node_id': 1},
+            'NodeHandler': {'obj_id': 1},
             'ReleaseHandler': {'obj_id': 1},
         }
         for handler in urls:
diff --git a/nailgun/nailgun/test/unit/test_node_deletion.py b/nailgun/nailgun/test/unit/test_node_deletion.py
index 8a33314449..6896355c95 100644
--- a/nailgun/nailgun/test/unit/test_node_deletion.py
+++ b/nailgun/nailgun/test/unit/test_node_deletion.py
@@ -48,7 +48,7 @@ class TestNodeDeletion(BaseIntegrationTest):
         resp = self.app.delete(
             reverse(
                 'NodeHandler',
-                kwargs={'node_id': node.id}),
+                kwargs={'obj_id': node.id}),
             headers=self.default_headers
         )
         self.assertEquals(204, resp.status_code)
diff --git a/nailgun/nailgun/test/unit/test_node_disks.py b/nailgun/nailgun/test/unit/test_node_disks.py
index 210fd2a83e..8374d99a5d 100644
--- a/nailgun/nailgun/test/unit/test_node_disks.py
+++ b/nailgun/nailgun/test/unit/test_node_disks.py
@@ -78,7 +78,11 @@ class TestNodeDisksHandlers(BaseIntegrationTest):
             self.assertEqual(len(disk['volumes']), 0)
 
     def test_volumes_regeneration_after_roles_update(self):
-        self.create_node(roles=[], pending_roles=['compute'])
+        self.env.create(
+            nodes_kwargs=[
+                {"roles": [], "pending_roles": ['compute']}
+            ]
+        )
         node_db = self.env.nodes[0]
         original_roles_response = self.get(node_db.id)
 
diff --git a/nailgun/nailgun/test/unit/test_node_nic_handler.py b/nailgun/nailgun/test/unit/test_node_nic_handler.py
index 9272aa97d8..0c8c7383e7 100644
--- a/nailgun/nailgun/test/unit/test_node_nic_handler.py
+++ b/nailgun/nailgun/test/unit/test_node_nic_handler.py
@@ -116,7 +116,7 @@ class TestHandlers(BaseIntegrationTest):
             )
             self.assertEquals(resp.status_code, 200)
             resp = self.app.get(
-                reverse('NodeHandler', kwargs={'node_id': node['id']}),
+                reverse('NodeHandler', kwargs={'obj_id': node['id']}),
                 headers=self.default_headers
             )
             ifaces = json.loads(resp.body)['meta']['interfaces']
diff --git a/nailgun/nailgun/volumes/manager.py b/nailgun/nailgun/volumes/manager.py
index 07791e1bb4..c1edd0aed0 100644
--- a/nailgun/nailgun/volumes/manager.py
+++ b/nailgun/nailgun/volumes/manager.py
@@ -918,8 +918,12 @@ class VolumeManager(object):
         disks_space = sum([d.size for d in self.disks])
         minimal_installation_size = self.__calc_minimal_installation_size()
 
-        self.__logger('Checking disks space: disks space %s, minimal size %s' %
-                      (disks_space, minimal_installation_size))
+        self.__logger(
+            'Checking disks space: disks space {0}, minimal size {1}'.format(
+                disks_space,
+                minimal_installation_size
+            )
+        )
 
         if disks_space < minimal_installation_size:
             raise errors.NotEnoughFreeSpace()