diff --git a/neutron/context.py b/neutron/context.py
index b9babba3b4c..5d7485808da 100644
--- a/neutron/context.py
+++ b/neutron/context.py
@@ -151,7 +151,7 @@ class Context(ContextBaseWithSession):
         if hasattr(super(Context, self), 'session'):
             return super(Context, self).session
         if self._session is None:
-            self._session = db_api.get_session()
+            self._session = db_api.get_writer_session()
         return self._session
 
 
diff --git a/neutron/db/api.py b/neutron/db/api.py
index 367c95ccf5d..f8ea2e399f8 100644
--- a/neutron/db/api.py
+++ b/neutron/db/api.py
@@ -16,6 +16,7 @@
 import contextlib
 import copy
 
+from debtcollector import removals
 from neutron_lib import exceptions
 from oslo_config import cfg
 from oslo_db import api as oslo_db_api
@@ -200,6 +201,9 @@ def exc_to_retry(etypes):
 
 #TODO(akamyshnikova): when all places in the code, which use sessions/
 # connections will be updated, this won't be needed
+@removals.remove(version='Ocata', removal_version='Pike',
+                 message="Usage of legacy facade is deprecated. Use "
+                         "get_reader_session or get_writer_session instead.")
 def get_session(autocommit=True, expire_on_commit=False, use_slave=False):
     """Helper method to grab session."""
     return context_manager.get_legacy_facade().get_session(
@@ -207,6 +211,16 @@ def get_session(autocommit=True, expire_on_commit=False, use_slave=False):
         use_slave=use_slave)
 
 
+def get_reader_session():
+    """Helper to get reader session"""
+    return context_manager.reader.get_sessionmaker()()
+
+
+def get_writer_session():
+    """Helper to get writer session"""
+    return context_manager.writer.get_sessionmaker()()
+
+
 @contextlib.contextmanager
 def autonested_transaction(sess):
     """This is a convenience method to not bother with 'nested' parameter."""
diff --git a/neutron/db/l3_hamode_db.py b/neutron/db/l3_hamode_db.py
index 7401f879625..6bb543808d6 100644
--- a/neutron/db/l3_hamode_db.py
+++ b/neutron/db/l3_hamode_db.py
@@ -752,7 +752,7 @@ def is_ha_router(router):
 
 
 def is_ha_router_port(context, device_owner, router_id):
-    session = db_api.get_session()
+    session = db_api.get_reader_session()
     if device_owner == constants.DEVICE_OWNER_HA_REPLICATED_INT:
         return True
     elif device_owner == constants.DEVICE_OWNER_ROUTER_SNAT:
diff --git a/neutron/plugins/ml2/drivers/l2pop/mech_driver.py b/neutron/plugins/ml2/drivers/l2pop/mech_driver.py
index 1892d9d9b95..74aa035b804 100644
--- a/neutron/plugins/ml2/drivers/l2pop/mech_driver.py
+++ b/neutron/plugins/ml2/drivers/l2pop/mech_driver.py
@@ -74,7 +74,7 @@ class L2populationMechanismDriver(api.MechanismDriver):
         fdb_entries = self._get_agent_fdb(
             context, context.bottom_bound_segment, port, agent_host)
         if port['device_owner'] in l2pop_db.HA_ROUTER_PORTS and fdb_entries:
-            session = db_api.get_session()
+            session = db_api.get_reader_session()
             network_id = port['network_id']
             other_fdb_ports = self._get_ha_port_agents_fdb(
                 session, network_id, port['device_id'])
@@ -111,7 +111,7 @@ class L2populationMechanismDriver(api.MechanismDriver):
         if not agent_host:
             return
 
-        agent_ip = l2pop_db.get_agent_ip_by_host(db_api.get_session(),
+        agent_ip = l2pop_db.get_agent_ip_by_host(db_api.get_reader_session(),
                                                  agent_host)
 
         orig_mac_ip = [l2pop_rpc.PortInfo(mac_address=port['mac_address'],
@@ -255,7 +255,7 @@ class L2populationMechanismDriver(api.MechanismDriver):
     def update_port_up(self, context):
         port = context.current
         agent_host = context.host
-        session = db_api.get_session()
+        session = db_api.get_reader_session()
         agent = l2pop_db.get_agent_by_host(session, agent_host)
         if not agent:
             LOG.warning(_LW("Unable to retrieve active L2 agent on host %s"),
@@ -306,11 +306,12 @@ class L2populationMechanismDriver(api.MechanismDriver):
 
         network_id = port['network_id']
 
-        session = db_api.get_session()
+        session = db_api.get_reader_session()
         agent_active_ports = l2pop_db.get_agent_network_active_port_count(
             session, agent_host, network_id)
 
-        agent = l2pop_db.get_agent_by_host(db_api.get_session(), agent_host)
+        agent = l2pop_db.get_agent_by_host(session,
+                                           agent_host)
         if not self._validate_segment(segment, port['id'], agent):
             return
 
diff --git a/neutron/plugins/ml2/drivers/type_tunnel.py b/neutron/plugins/ml2/drivers/type_tunnel.py
index 5fa97751e75..d1cf3434109 100644
--- a/neutron/plugins/ml2/drivers/type_tunnel.py
+++ b/neutron/plugins/ml2/drivers/type_tunnel.py
@@ -28,6 +28,7 @@ from sqlalchemy import or_
 
 from neutron._i18n import _, _LI, _LW
 from neutron.common import topics
+from neutron import context
 from neutron.db import api as db_api
 from neutron.plugins.common import constants as p_const
 from neutron.plugins.common import utils as plugin_utils
@@ -146,12 +147,12 @@ class _TunnelTypeDriverBase(helpers.SegmentTypeDriver):
 
         tunnel_id_getter = operator.attrgetter(self.segmentation_key)
         tunnel_col = getattr(self.model, self.segmentation_key)
-        session = db_api.get_session()
-        with session.begin(subtransactions=True):
+        ctx = context.get_admin_context()
+        with db_api.context_manager.writer.using(ctx):
             # remove from table unallocated tunnels not currently allocatable
             # fetch results as list via all() because we'll be iterating
             # through them twice
-            allocs = (session.query(self.model).
+            allocs = (ctx.session.query(self.model).
                       with_lockmode("update").all())
 
             # collect those vnis that needs to be deleted from db
@@ -161,7 +162,7 @@ class _TunnelTypeDriverBase(helpers.SegmentTypeDriver):
             # Immediately delete tunnels in chunks. This leaves no work for
             # flush at the end of transaction
             for chunk in chunks(to_remove, self.BULK_SIZE):
-                session.query(self.model).filter(
+                ctx.session.query(self.model).filter(
                     tunnel_col.in_(chunk)).delete(synchronize_session=False)
 
             # collect vnis that need to be added
@@ -170,7 +171,7 @@ class _TunnelTypeDriverBase(helpers.SegmentTypeDriver):
             for chunk in chunks(missings, self.BULK_SIZE):
                 bulk = [{self.segmentation_key: x, 'allocated': False}
                         for x in chunk]
-                session.execute(self.model.__table__.insert(), bulk)
+                ctx.session.execute(self.model.__table__.insert(), bulk)
 
     def is_partial_segment(self, segment):
         return segment.get(api.SEGMENTATION_ID) is None
@@ -346,40 +347,37 @@ class EndpointTunnelTypeDriver(ML2TunnelTypeDriver):
 
     def get_endpoint_by_host(self, host):
         LOG.debug("get_endpoint_by_host() called for host %s", host)
-        session = db_api.get_session()
+        session = db_api.get_reader_session()
         return (session.query(self.endpoint_model).
                 filter_by(host=host).first())
 
     def get_endpoint_by_ip(self, ip):
         LOG.debug("get_endpoint_by_ip() called for ip %s", ip)
-        session = db_api.get_session()
+        session = db_api.get_reader_session()
         return (session.query(self.endpoint_model).
                 filter_by(ip_address=ip).first())
 
     def delete_endpoint(self, ip):
         LOG.debug("delete_endpoint() called for ip %s", ip)
-        session = db_api.get_session()
-        with session.begin(subtransactions=True):
-            (session.query(self.endpoint_model).
-             filter_by(ip_address=ip).delete())
+        session = db_api.get_writer_session()
+        session.query(self.endpoint_model).filter_by(ip_address=ip).delete()
 
     def delete_endpoint_by_host_or_ip(self, host, ip):
         LOG.debug("delete_endpoint_by_host_or_ip() called for "
                   "host %(host)s or %(ip)s", {'host': host, 'ip': ip})
-        session = db_api.get_session()
-        with session.begin(subtransactions=True):
-            session.query(self.endpoint_model).filter(
-                    or_(self.endpoint_model.host == host,
-                        self.endpoint_model.ip_address == ip)).delete()
+        session = db_api.get_writer_session()
+        session.query(self.endpoint_model).filter(
+            or_(self.endpoint_model.host == host,
+                self.endpoint_model.ip_address == ip)).delete()
 
     def _get_endpoints(self):
         LOG.debug("_get_endpoints() called")
-        session = db_api.get_session()
+        session = db_api.get_reader_session()
         return session.query(self.endpoint_model)
 
     def _add_endpoint(self, ip, host, **kwargs):
         LOG.debug("_add_endpoint() called for ip %s", ip)
-        session = db_api.get_session()
+        session = db_api.get_writer_session()
         try:
             endpoint = self.endpoint_model(ip_address=ip, host=host, **kwargs)
             endpoint.save(session)
diff --git a/neutron/plugins/ml2/drivers/type_vlan.py b/neutron/plugins/ml2/drivers/type_vlan.py
index f52c0d1997b..eecdb6f07fc 100644
--- a/neutron/plugins/ml2/drivers/type_vlan.py
+++ b/neutron/plugins/ml2/drivers/type_vlan.py
@@ -23,6 +23,7 @@ from six import moves
 from neutron._i18n import _, _LE, _LI, _LW
 from neutron.common import _deprecate
 from neutron.conf.plugins.ml2.drivers import driver_type
+from neutron import context
 from neutron.db import api as db_api
 from neutron.db.models.plugins.ml2 import vlanallocation as vlan_alloc_model
 from neutron.plugins.common import constants as p_const
@@ -64,11 +65,11 @@ class VlanTypeDriver(helpers.SegmentTypeDriver):
 
     @db_api.retry_db_errors
     def _sync_vlan_allocations(self):
-        session = db_api.get_session()
-        with session.begin(subtransactions=True):
+        ctx = context.get_admin_context()
+        with db_api.context_manager.writer.using(ctx):
             # get existing allocations for all physical networks
             allocations = dict()
-            allocs = (session.query(vlan_alloc_model.VlanAllocation).
+            allocs = (ctx.session.query(vlan_alloc_model.VlanAllocation).
                       with_lockmode('update'))
             for alloc in allocs:
                 if alloc.physical_network not in allocations:
@@ -101,7 +102,7 @@ class VlanTypeDriver(helpers.SegmentTypeDriver):
                                           {'vlan_id': alloc.vlan_id,
                                            'physical_network':
                                            physical_network})
-                                session.delete(alloc)
+                                ctx.session.delete(alloc)
                     del allocations[physical_network]
 
                 # add missing allocatable vlans to table
@@ -110,7 +111,7 @@ class VlanTypeDriver(helpers.SegmentTypeDriver):
                                            physical_network=physical_network,
                                            vlan_id=vlan_id,
                                            allocated=False)
-                    session.add(alloc)
+                    ctx.session.add(alloc)
 
             # remove from table unallocated vlans for any unconfigured
             # physical networks
@@ -122,7 +123,7 @@ class VlanTypeDriver(helpers.SegmentTypeDriver):
                                   {'vlan_id': alloc.vlan_id,
                                    'physical_network':
                                    alloc.physical_network})
-                        session.delete(alloc)
+                        ctx.session.delete(alloc)
 
     def get_type(self):
         return p_const.TYPE_VLAN
diff --git a/neutron/plugins/ml2/plugin.py b/neutron/plugins/ml2/plugin.py
index 14c45aa020d..1c55a373d62 100644
--- a/neutron/plugins/ml2/plugin.py
+++ b/neutron/plugins/ml2/plugin.py
@@ -590,20 +590,16 @@ class Ml2Plugin(db_base_plugin_v2.NeutronDbPluginV2,
                attributes.SUBNETS, ['_ml2_md_extend_subnet_dict'])
 
     def _ml2_md_extend_network_dict(self, result, netdb):
-        session = db_api.get_session()
-        with session.begin(subtransactions=True):
-            self.extension_manager.extend_network_dict(session, netdb, result)
+        session = db_api.get_reader_session()
+        self.extension_manager.extend_network_dict(session, netdb, result)
 
     def _ml2_md_extend_port_dict(self, result, portdb):
-        session = db_api.get_session()
-        with session.begin(subtransactions=True):
-            self.extension_manager.extend_port_dict(session, portdb, result)
+        session = db_api.get_reader_session()
+        self.extension_manager.extend_port_dict(session, portdb, result)
 
     def _ml2_md_extend_subnet_dict(self, result, subnetdb):
-        session = db_api.get_session()
-        with session.begin(subtransactions=True):
-            self.extension_manager.extend_subnet_dict(
-                session, subnetdb, result)
+        session = db_api.get_reader_session()
+        self.extension_manager.extend_subnet_dict(session, subnetdb, result)
 
     # Note - The following hook methods have "ml2" in their names so
     # that they are not called twice during unit tests due to global
diff --git a/neutron/tests/unit/db/test_db_base_plugin_v2.py b/neutron/tests/unit/db/test_db_base_plugin_v2.py
index c88a217049d..b429f589ca1 100644
--- a/neutron/tests/unit/db/test_db_base_plugin_v2.py
+++ b/neutron/tests/unit/db/test_db_base_plugin_v2.py
@@ -6466,7 +6466,7 @@ class DbOperationBoundMixin(object):
         def _event_incrementer(*args, **kwargs):
             self._db_execute_count += 1
 
-        engine = db_api.context_manager.get_legacy_facade().get_engine()
+        engine = db_api.context_manager.writer.get_engine()
         event.listen(engine, 'after_execute', _event_incrementer)
         self.addCleanup(event.remove, engine, 'after_execute',
                         _event_incrementer)
diff --git a/neutron/tests/unit/extensions/test_flavors.py b/neutron/tests/unit/extensions/test_flavors.py
index 2336ad5c0fd..163e725ddf3 100644
--- a/neutron/tests/unit/extensions/test_flavors.py
+++ b/neutron/tests/unit/extensions/test_flavors.py
@@ -458,7 +458,7 @@ class FlavorPluginTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase,
             self.service_manager.add_provider_configuration(
                 provider.split(':')[0], provconf.ProviderConfiguration())
 
-        dbapi.context_manager.get_legacy_facade().get_engine()
+        dbapi.context_manager.writer.get_engine()
 
     def _create_flavor(self, description=None):
         flavor = {'flavor': {'name': 'GOLD',
diff --git a/neutron/tests/unit/extensions/test_l3_ext_gw_mode.py b/neutron/tests/unit/extensions/test_l3_ext_gw_mode.py
index a5bf260a5b2..561c5c9881a 100644
--- a/neutron/tests/unit/extensions/test_l3_ext_gw_mode.py
+++ b/neutron/tests/unit/extensions/test_l3_ext_gw_mode.py
@@ -126,7 +126,7 @@ class TestL3GwModeMixin(testlib_api.SqlTestCase):
         self.context = mock_context.get_admin_context()
         # This ensure also calls to elevated work in unit tests
         self.context.elevated.return_value = self.context
-        self.context.session = db_api.get_session()
+        self.context.session = db_api.get_writer_session()
         # Create sample data for tests
         self.ext_net_id = _uuid()
         self.int_net_id = _uuid()
diff --git a/neutron/tests/unit/plugins/ml2/test_plugin.py b/neutron/tests/unit/plugins/ml2/test_plugin.py
index 730fa8cc729..3d91d6c0d1f 100644
--- a/neutron/tests/unit/plugins/ml2/test_plugin.py
+++ b/neutron/tests/unit/plugins/ml2/test_plugin.py
@@ -1166,7 +1166,7 @@ class TestMl2PortsV2(test_plugin.TestPortsV2, Ml2PluginV2TestCase):
                     raise db_exc.DBDuplicateEntry()
 
         listener = IPAllocationsGrenade()
-        engine = db_api.context_manager.get_legacy_facade().get_engine()
+        engine = db_api.context_manager.writer.get_engine()
         event.listen(engine, 'before_cursor_execute', listener.execute)
         event.listen(engine, 'commit', listener.commit)
         self.addCleanup(event.remove, engine, 'before_cursor_execute',
diff --git a/neutron/tests/unit/quota/test_resource.py b/neutron/tests/unit/quota/test_resource.py
index 4b2cadbb730..93f6da4a4d6 100644
--- a/neutron/tests/unit/quota/test_resource.py
+++ b/neutron/tests/unit/quota/test_resource.py
@@ -60,7 +60,7 @@ class TestResource(base.DietTestCase):
 class TestTrackedResource(testlib_api.SqlTestCaseLight):
 
     def _add_data(self, tenant_id=None):
-        session = db_api.get_session()
+        session = db_api.get_writer_session()
         with session.begin():
             tenant_id = tenant_id or self.tenant_id
             session.add(test_quota.MehModel(
@@ -71,7 +71,7 @@ class TestTrackedResource(testlib_api.SqlTestCaseLight):
                 tenant_id=tenant_id))
 
     def _delete_data(self):
-        session = db_api.get_session()
+        session = db_api.get_writer_session()
         with session.begin():
             query = session.query(test_quota.MehModel).filter_by(
                 tenant_id=self.tenant_id)
@@ -79,7 +79,7 @@ class TestTrackedResource(testlib_api.SqlTestCaseLight):
                 session.delete(item)
 
     def _update_data(self):
-        session = db_api.get_session()
+        session = db_api.get_writer_session()
         with session.begin():
             query = session.query(test_quota.MehModel).filter_by(
                 tenant_id=self.tenant_id)
diff --git a/neutron/tests/unit/services/metering/test_metering_plugin.py b/neutron/tests/unit/services/metering/test_metering_plugin.py
index 058474b6921..5a29da97e97 100644
--- a/neutron/tests/unit/services/metering/test_metering_plugin.py
+++ b/neutron/tests/unit/services/metering/test_metering_plugin.py
@@ -67,7 +67,7 @@ class FakeContext(context.ContextBaseWithSession):
     @property
     def session(self):
         if self._session is None:
-            self._session = db_api.get_session()
+            self._session = db_api.get_writer_session()
         return self._session
 
 
diff --git a/neutron/tests/unit/test_context.py b/neutron/tests/unit/test_context.py
index ec15e33ecf4..8fd906a03b8 100644
--- a/neutron/tests/unit/test_context.py
+++ b/neutron/tests/unit/test_context.py
@@ -25,7 +25,7 @@ class TestNeutronContext(base.BaseTestCase):
 
     def setUp(self):
         super(TestNeutronContext, self).setUp()
-        db_api = 'neutron.db.api.get_session'
+        db_api = 'neutron.db.api.get_writer_session'
         self._db_api_session_patcher = mock.patch(db_api)
         self.db_api_session = self._db_api_session_patcher.start()
 
diff --git a/neutron/tests/unit/testlib_api.py b/neutron/tests/unit/testlib_api.py
index 64052a8c8da..ef97ebc108d 100644
--- a/neutron/tests/unit/testlib_api.py
+++ b/neutron/tests/unit/testlib_api.py
@@ -107,7 +107,7 @@ class SqlFixture(fixtures.Fixture):
 
         db_api.context_manager._root_factory = self.enginefacade_factory
 
-        engine = db_api.context_manager.get_legacy_facade().get_engine()
+        engine = db_api.context_manager.writer.get_engine()
 
         self.addCleanup(
             lambda: setattr(