code: def update_vpc_entry(nexus_ips, vpc_id, learned, active):
      
  
      LOG.debug("update_vpc_entry called")
  
      session = bc.get_writer_session()
  
      with session.begin():
          for n_ip in nexus_ips:
              flipit = not active
              x = session.execute(
                  sa.update(nexus_models_v2.NexusVPCAlloc).values({
                      'learned': learned,
                      'active': active}).where(sa.and_(
                          nexus_models_v2.NexusVPCAlloc.switch_ip == n_ip,
                          nexus_models_v2.NexusVPCAlloc.vpc_id == vpc_id,
                          nexus_models_v2.NexusVPCAlloc.active == flipit
                      )))
              if x.rowcount != 1:
                  raise c_exc.NexusVPCAllocNotFound(
                      switch_ip=n_ip, vpc_id=vpc_id, active=active)
docs: Change active state in vpc_allocate data base.