Example #1
0
// CreateNetwork creates and returns a Network based on the provided NetworkSpec.
// - Returns `InvalidArgument` if the NetworkSpec is malformed.
// - Returns an error if the creation fails.
func (s *Server) CreateNetwork(ctx context.Context, request *api.CreateNetworkRequest) (*api.CreateNetworkResponse, error) {
	// if you change this function, you have to change createInternalNetwork in
	// the tests to match it (except the part where we check the label).
	if err := validateNetworkSpec(request.Spec, s.pg); err != nil {
		return nil, err
	}

	if _, ok := request.Spec.Annotations.Labels["com.docker.swarm.internal"]; ok {
		return nil, grpc.Errorf(codes.PermissionDenied, "label com.docker.swarm.internal is for predefined internal networks and cannot be applied by users")
	}

	// TODO(mrjana): Consider using `Name` as a primary key to handle
	// duplicate creations. See #65
	n := &api.Network{
		ID:   identity.NewID(),
		Spec: *request.Spec,
	}

	err := s.store.Update(func(tx store.Tx) error {
		return store.CreateNetwork(tx, n)
	})
	if err != nil {
		return nil, err
	}

	return &api.CreateNetworkResponse{
		Network: n,
	}, nil
}
Example #2
0
// createInternalNetwork creates an internal network for testing. it is the same
// as Server.CreateNetwork except without the label check.
func (s *Server) createInternalNetwork(ctx context.Context, request *api.CreateNetworkRequest) (*api.CreateNetworkResponse, error) {
	if err := validateNetworkSpec(request.Spec); err != nil {
		return nil, err
	}

	// TODO(mrjana): Consider using `Name` as a primary key to handle
	// duplicate creations. See #65
	n := &api.Network{
		ID:   identity.NewID(),
		Spec: *request.Spec,
	}

	err := s.store.Update(func(tx store.Tx) error {
		return store.CreateNetwork(tx, n)
	})
	if err != nil {
		return nil, err
	}

	return &api.CreateNetworkResponse{
		Network: n,
	}, nil
}
Example #3
0
func (a *Allocator) doNetworkInit(ctx context.Context) (err error) {
	na, err := networkallocator.New()
	if err != nil {
		return err
	}

	nc := &networkContext{
		nwkAllocator:        na,
		unallocatedTasks:    make(map[string]*api.Task),
		unallocatedServices: make(map[string]*api.Service),
		unallocatedNetworks: make(map[string]*api.Network),
		ingressNetwork:      newIngressNetwork(),
	}
	a.netCtx = nc
	defer func() {
		// Clear a.netCtx if initialization was unsuccessful.
		if err != nil {
			a.netCtx = nil
		}
	}()

	// Check if we have the ingress network. If not found create
	// it before reading all network objects for allocation.
	var networks []*api.Network
	a.store.View(func(tx store.ReadTx) {
		networks, err = store.FindNetworks(tx, store.ByName(ingressNetworkName))
		if len(networks) > 0 {
			nc.ingressNetwork = networks[0]
		}
	})
	if err != nil {
		return errors.Wrap(err, "failed to find ingress network during init")
	}

	// If ingress network is not found, create one right away
	// using the predefined template.
	if len(networks) == 0 {
		if err := a.store.Update(func(tx store.Tx) error {
			nc.ingressNetwork.ID = identity.NewID()
			if err := store.CreateNetwork(tx, nc.ingressNetwork); err != nil {
				return err
			}

			return nil
		}); err != nil {
			return errors.Wrap(err, "failed to create ingress network")
		}

		a.store.View(func(tx store.ReadTx) {
			networks, err = store.FindNetworks(tx, store.ByName(ingressNetworkName))
			if len(networks) > 0 {
				nc.ingressNetwork = networks[0]
			}
		})
		if err != nil {
			return errors.Wrap(err, "failed to find ingress network after creating it")
		}

	}

	// Try to complete ingress network allocation before anything else so
	// that the we can get the preferred subnet for ingress
	// network.
	if !na.IsAllocated(nc.ingressNetwork) {
		if err := a.allocateNetwork(ctx, nc.ingressNetwork); err != nil {
			log.G(ctx).WithError(err).Error("failed allocating ingress network during init")
		} else if _, err := a.store.Batch(func(batch *store.Batch) error {
			if err := a.commitAllocatedNetwork(ctx, batch, nc.ingressNetwork); err != nil {
				log.G(ctx).WithError(err).Error("failed committing allocation of ingress network during init")
			}
			return nil
		}); err != nil {
			log.G(ctx).WithError(err).Error("failed committing allocation of ingress network during init")
		}
	}

	// Allocate networks in the store so far before we started
	// watching.
	a.store.View(func(tx store.ReadTx) {
		networks, err = store.FindNetworks(tx, store.All)
	})
	if err != nil {
		return errors.Wrap(err, "error listing all networks in store while trying to allocate during init")
	}

	var allocatedNetworks []*api.Network
	for _, n := range networks {
		if na.IsAllocated(n) {
			continue
		}

		if err := a.allocateNetwork(ctx, n); err != nil {
			log.G(ctx).WithError(err).Errorf("failed allocating network %s during init", n.ID)
			continue
		}
		allocatedNetworks = append(allocatedNetworks, n)
	}

	if _, err := a.store.Batch(func(batch *store.Batch) error {
		for _, n := range allocatedNetworks {
			if err := a.commitAllocatedNetwork(ctx, batch, n); err != nil {
				log.G(ctx).WithError(err).Errorf("failed committing allocation of network %s during init", n.ID)
			}
		}
		return nil
	}); err != nil {
		log.G(ctx).WithError(err).Error("failed committing allocation of networks during init")
	}

	// Allocate nodes in the store so far before we process watched events.
	var nodes []*api.Node
	a.store.View(func(tx store.ReadTx) {
		nodes, err = store.FindNodes(tx, store.All)
	})
	if err != nil {
		return errors.Wrap(err, "error listing all nodes in store while trying to allocate during init")
	}

	var allocatedNodes []*api.Node
	for _, node := range nodes {
		if na.IsNodeAllocated(node) {
			continue
		}

		if node.Attachment == nil {
			node.Attachment = &api.NetworkAttachment{}
		}

		node.Attachment.Network = nc.ingressNetwork.Copy()
		if err := a.allocateNode(ctx, node); err != nil {
			log.G(ctx).WithError(err).Errorf("Failed to allocate network resources for node %s during init", node.ID)
			continue
		}

		allocatedNodes = append(allocatedNodes, node)
	}

	if _, err := a.store.Batch(func(batch *store.Batch) error {
		for _, node := range allocatedNodes {
			if err := a.commitAllocatedNode(ctx, batch, node); err != nil {
				log.G(ctx).WithError(err).Errorf("Failed to commit allocation of network resources for node %s during init", node.ID)
			}
		}
		return nil
	}); err != nil {
		log.G(ctx).WithError(err).Error("Failed to commit allocation of network resources for nodes during init")
	}

	// Allocate services in the store so far before we process watched events.
	var services []*api.Service
	a.store.View(func(tx store.ReadTx) {
		services, err = store.FindServices(tx, store.All)
	})
	if err != nil {
		return errors.Wrap(err, "error listing all services in store while trying to allocate during init")
	}

	var allocatedServices []*api.Service
	for _, s := range services {
		if nc.nwkAllocator.IsServiceAllocated(s) {
			continue
		}

		if err := a.allocateService(ctx, s); err != nil {
			log.G(ctx).WithError(err).Errorf("failed allocating service %s during init", s.ID)
			continue
		}
		allocatedServices = append(allocatedServices, s)
	}

	if _, err := a.store.Batch(func(batch *store.Batch) error {
		for _, s := range allocatedServices {
			if err := a.commitAllocatedService(ctx, batch, s); err != nil {
				log.G(ctx).WithError(err).Errorf("failed committing allocation of service %s during init", s.ID)
			}
		}
		return nil
	}); err != nil {
		log.G(ctx).WithError(err).Error("failed committing allocation of services during init")
	}

	// Allocate tasks in the store so far before we started watching.
	var (
		tasks          []*api.Task
		allocatedTasks []*api.Task
	)
	a.store.View(func(tx store.ReadTx) {
		tasks, err = store.FindTasks(tx, store.All)
	})
	if err != nil {
		return errors.Wrap(err, "error listing all tasks in store while trying to allocate during init")
	}

	for _, t := range tasks {
		if taskDead(t) {
			continue
		}

		var s *api.Service
		if t.ServiceID != "" {
			a.store.View(func(tx store.ReadTx) {
				s = store.GetService(tx, t.ServiceID)
			})
		}

		// Populate network attachments in the task
		// based on service spec.
		a.taskCreateNetworkAttachments(t, s)

		if taskReadyForNetworkVote(t, s, nc) {
			if t.Status.State >= api.TaskStatePending {
				continue
			}

			if a.taskAllocateVote(networkVoter, t.ID) {
				// If the task is not attached to any network, network
				// allocators job is done. Immediately cast a vote so
				// that the task can be moved to ALLOCATED state as
				// soon as possible.
				allocatedTasks = append(allocatedTasks, t)
			}
			continue
		}

		err := a.allocateTask(ctx, t)
		if err == nil {
			allocatedTasks = append(allocatedTasks, t)
		} else if err != errNoChanges {
			log.G(ctx).WithError(err).Errorf("failed allocating task %s during init", t.ID)
			nc.unallocatedTasks[t.ID] = t
		}
	}

	if _, err := a.store.Batch(func(batch *store.Batch) error {
		for _, t := range allocatedTasks {
			if err := a.commitAllocatedTask(ctx, batch, t); err != nil {
				log.G(ctx).WithError(err).Errorf("failed committing allocation of task %s during init", t.ID)
			}
		}

		return nil
	}); err != nil {
		log.G(ctx).WithError(err).Error("failed committing allocation of tasks during init")
	}

	return nil
}
Example #4
0
func TestAllocator(t *testing.T) {
	s := store.NewMemoryStore(nil)
	assert.NotNil(t, s)
	defer s.Close()

	a, err := New(s)
	assert.NoError(t, err)
	assert.NotNil(t, a)

	// Try adding some objects to store before allocator is started
	assert.NoError(t, s.Update(func(tx store.Tx) error {
		n1 := &api.Network{
			ID: "testID1",
			Spec: api.NetworkSpec{
				Annotations: api.Annotations{
					Name: "test1",
				},
			},
		}
		assert.NoError(t, store.CreateNetwork(tx, n1))

		s1 := &api.Service{
			ID: "testServiceID1",
			Spec: api.ServiceSpec{
				Annotations: api.Annotations{
					Name: "service1",
				},
				Task: api.TaskSpec{
					Networks: []*api.NetworkAttachmentConfig{
						{
							Target: "testID1",
						},
					},
				},
				Endpoint: &api.EndpointSpec{},
			},
		}
		assert.NoError(t, store.CreateService(tx, s1))

		t1 := &api.Task{
			ID: "testTaskID1",
			Status: api.TaskStatus{
				State: api.TaskStateNew,
			},
			Networks: []*api.NetworkAttachment{
				{
					Network: n1,
				},
			},
		}
		assert.NoError(t, store.CreateTask(tx, t1))
		return nil
	}))

	netWatch, cancel := state.Watch(s.WatchQueue(), state.EventUpdateNetwork{}, state.EventDeleteNetwork{})
	defer cancel()
	taskWatch, cancel := state.Watch(s.WatchQueue(), state.EventUpdateTask{}, state.EventDeleteTask{})
	defer cancel()
	serviceWatch, cancel := state.Watch(s.WatchQueue(), state.EventUpdateService{}, state.EventDeleteService{})
	defer cancel()

	// Start allocator
	go func() {
		assert.NoError(t, a.Run(context.Background()))
	}()

	// Now verify if we get network and tasks updated properly
	watchNetwork(t, netWatch, false, isValidNetwork)
	watchTask(t, s, taskWatch, false, isValidTask)
	watchService(t, serviceWatch, false, nil)

	// Add new networks/tasks/services after allocator is started.
	assert.NoError(t, s.Update(func(tx store.Tx) error {
		n2 := &api.Network{
			ID: "testID2",
			Spec: api.NetworkSpec{
				Annotations: api.Annotations{
					Name: "test2",
				},
			},
		}
		assert.NoError(t, store.CreateNetwork(tx, n2))
		return nil
	}))

	watchNetwork(t, netWatch, false, isValidNetwork)

	assert.NoError(t, s.Update(func(tx store.Tx) error {
		s2 := &api.Service{
			ID: "testServiceID2",
			Spec: api.ServiceSpec{
				Annotations: api.Annotations{
					Name: "service2",
				},
				Networks: []*api.NetworkAttachmentConfig{
					{
						Target: "testID2",
					},
				},
				Endpoint: &api.EndpointSpec{},
			},
		}
		assert.NoError(t, store.CreateService(tx, s2))
		return nil
	}))

	watchService(t, serviceWatch, false, nil)

	assert.NoError(t, s.Update(func(tx store.Tx) error {
		t2 := &api.Task{
			ID: "testTaskID2",
			Status: api.TaskStatus{
				State: api.TaskStateNew,
			},
			ServiceID:    "testServiceID2",
			DesiredState: api.TaskStateRunning,
		}
		assert.NoError(t, store.CreateTask(tx, t2))
		return nil
	}))

	watchTask(t, s, taskWatch, false, isValidTask)

	// Now try adding a task which depends on a network before adding the network.
	n3 := &api.Network{
		ID: "testID3",
		Spec: api.NetworkSpec{
			Annotations: api.Annotations{
				Name: "test3",
			},
		},
	}

	assert.NoError(t, s.Update(func(tx store.Tx) error {
		t3 := &api.Task{
			ID: "testTaskID3",
			Status: api.TaskStatus{
				State: api.TaskStateNew,
			},
			DesiredState: api.TaskStateRunning,
			Networks: []*api.NetworkAttachment{
				{
					Network: n3,
				},
			},
		}
		assert.NoError(t, store.CreateTask(tx, t3))
		return nil
	}))

	// Wait for a little bit of time before adding network just to
	// test network is not available while task allocation is
	// going through
	time.Sleep(10 * time.Millisecond)

	assert.NoError(t, s.Update(func(tx store.Tx) error {
		assert.NoError(t, store.CreateNetwork(tx, n3))
		return nil
	}))

	watchNetwork(t, netWatch, false, isValidNetwork)
	watchTask(t, s, taskWatch, false, isValidTask)

	assert.NoError(t, s.Update(func(tx store.Tx) error {
		assert.NoError(t, store.DeleteTask(tx, "testTaskID3"))
		return nil
	}))
	watchTask(t, s, taskWatch, false, isValidTask)

	assert.NoError(t, s.Update(func(tx store.Tx) error {
		t5 := &api.Task{
			ID: "testTaskID5",
			Spec: api.TaskSpec{
				Networks: []*api.NetworkAttachmentConfig{
					{
						Target: "testID2",
					},
				},
			},
			Status: api.TaskStatus{
				State: api.TaskStateNew,
			},
			DesiredState: api.TaskStateRunning,
			ServiceID:    "testServiceID2",
		}
		assert.NoError(t, store.CreateTask(tx, t5))
		return nil
	}))
	watchTask(t, s, taskWatch, false, isValidTask)

	assert.NoError(t, s.Update(func(tx store.Tx) error {
		assert.NoError(t, store.DeleteNetwork(tx, "testID3"))
		return nil
	}))
	watchNetwork(t, netWatch, false, isValidNetwork)

	assert.NoError(t, s.Update(func(tx store.Tx) error {
		assert.NoError(t, store.DeleteService(tx, "testServiceID2"))
		return nil
	}))
	watchService(t, serviceWatch, false, nil)

	// Try to create a task with no network attachments and test
	// that it moves to ALLOCATED state.
	assert.NoError(t, s.Update(func(tx store.Tx) error {
		t4 := &api.Task{
			ID: "testTaskID4",
			Status: api.TaskStatus{
				State: api.TaskStateNew,
			},
			DesiredState: api.TaskStateRunning,
		}
		assert.NoError(t, store.CreateTask(tx, t4))
		return nil
	}))
	watchTask(t, s, taskWatch, false, isValidTask)

	assert.NoError(t, s.Update(func(tx store.Tx) error {
		n2 := store.GetNetwork(tx, "testID2")
		require.NotEqual(t, nil, n2)
		assert.NoError(t, store.UpdateNetwork(tx, n2))
		return nil
	}))
	watchNetwork(t, netWatch, false, isValidNetwork)
	watchNetwork(t, netWatch, true, nil)

	// Try updating task which is already allocated
	assert.NoError(t, s.Update(func(tx store.Tx) error {
		t2 := store.GetTask(tx, "testTaskID2")
		require.NotEqual(t, nil, t2)
		assert.NoError(t, store.UpdateTask(tx, t2))
		return nil
	}))
	watchTask(t, s, taskWatch, false, isValidTask)
	watchTask(t, s, taskWatch, true, nil)

	// Try adding networks with conflicting network resources and
	// add task which attaches to a network which gets allocated
	// later and verify if task reconciles and moves to ALLOCATED.
	n4 := &api.Network{
		ID: "testID4",
		Spec: api.NetworkSpec{
			Annotations: api.Annotations{
				Name: "test4",
			},
			DriverConfig: &api.Driver{
				Name: "overlay",
				Options: map[string]string{
					"com.docker.network.driver.overlay.vxlanid_list": "328",
				},
			},
		},
	}

	n5 := n4.Copy()
	n5.ID = "testID5"
	n5.Spec.Annotations.Name = "test5"
	assert.NoError(t, s.Update(func(tx store.Tx) error {
		assert.NoError(t, store.CreateNetwork(tx, n4))
		return nil
	}))
	watchNetwork(t, netWatch, false, isValidNetwork)

	assert.NoError(t, s.Update(func(tx store.Tx) error {
		assert.NoError(t, store.CreateNetwork(tx, n5))
		return nil
	}))
	watchNetwork(t, netWatch, true, nil)

	assert.NoError(t, s.Update(func(tx store.Tx) error {
		t6 := &api.Task{
			ID: "testTaskID6",
			Status: api.TaskStatus{
				State: api.TaskStateNew,
			},
			DesiredState: api.TaskStateRunning,
			Networks: []*api.NetworkAttachment{
				{
					Network: n5,
				},
			},
		}
		assert.NoError(t, store.CreateTask(tx, t6))
		return nil
	}))
	watchTask(t, s, taskWatch, true, nil)

	// Now remove the conflicting network.
	assert.NoError(t, s.Update(func(tx store.Tx) error {
		assert.NoError(t, store.DeleteNetwork(tx, n4.ID))
		return nil
	}))
	watchNetwork(t, netWatch, false, isValidNetwork)
	watchTask(t, s, taskWatch, false, isValidTask)

	// Try adding services with conflicting port configs and add
	// task which is part of the service whose allocation hasn't
	// happened and when that happens later and verify if task
	// reconciles and moves to ALLOCATED.
	s3 := &api.Service{
		ID: "testServiceID3",
		Spec: api.ServiceSpec{
			Annotations: api.Annotations{
				Name: "service3",
			},
			Endpoint: &api.EndpointSpec{
				Ports: []*api.PortConfig{
					{
						Name:          "http",
						TargetPort:    80,
						PublishedPort: 8080,
					},
				},
			},
		},
	}

	s4 := s3.Copy()
	s4.ID = "testServiceID4"
	s4.Spec.Annotations.Name = "service4"
	assert.NoError(t, s.Update(func(tx store.Tx) error {
		assert.NoError(t, store.CreateService(tx, s3))
		return nil
	}))
	watchService(t, serviceWatch, false, nil)
	assert.NoError(t, s.Update(func(tx store.Tx) error {
		assert.NoError(t, store.CreateService(tx, s4))
		return nil
	}))
	watchService(t, serviceWatch, true, nil)

	assert.NoError(t, s.Update(func(tx store.Tx) error {
		t7 := &api.Task{
			ID: "testTaskID7",
			Status: api.TaskStatus{
				State: api.TaskStateNew,
			},
			ServiceID:    "testServiceID4",
			DesiredState: api.TaskStateRunning,
		}
		assert.NoError(t, store.CreateTask(tx, t7))
		return nil
	}))
	watchTask(t, s, taskWatch, true, nil)

	// Now remove the conflicting service.
	assert.NoError(t, s.Update(func(tx store.Tx) error {
		assert.NoError(t, store.DeleteService(tx, s3.ID))
		return nil
	}))
	watchService(t, serviceWatch, false, nil)
	watchTask(t, s, taskWatch, false, isValidTask)

	a.Stop()
}
Example #5
0
func (a *Allocator) doNetworkInit(ctx context.Context) error {
	na, err := networkallocator.New()
	if err != nil {
		return err
	}

	nc := &networkContext{
		nwkAllocator:        na,
		unallocatedTasks:    make(map[string]*api.Task),
		unallocatedServices: make(map[string]*api.Service),
		unallocatedNetworks: make(map[string]*api.Network),
	}

	// Check if we have the ingress network. If not found create
	// it before reading all network objects for allocation.
	var networks []*api.Network
	a.store.View(func(tx store.ReadTx) {
		networks, err = store.FindNetworks(tx, store.ByName(ingressNetworkName))
		if len(networks) > 0 {
			ingressNetwork = networks[0]
		}
	})
	if err != nil {
		return fmt.Errorf("failed to find ingress network during init: %v", err)
	}

	// If ingress network is not found, create one right away
	// using the predefined template.
	if len(networks) == 0 {
		if err := a.store.Update(func(tx store.Tx) error {
			ingressNetwork.ID = identity.NewID()
			if err := store.CreateNetwork(tx, ingressNetwork); err != nil {
				return err
			}

			return nil
		}); err != nil {
			return fmt.Errorf("failed to create ingress network: %v", err)
		}

		a.store.View(func(tx store.ReadTx) {
			networks, err = store.FindNetworks(tx, store.ByName(ingressNetworkName))
			if len(networks) > 0 {
				ingressNetwork = networks[0]
			}
		})
		if err != nil {
			return fmt.Errorf("failed to find ingress network after creating it: %v", err)
		}

	}

	// Try to complete ingress network allocation before anything else so
	// that the we can get the preferred subnet for ingress
	// network.
	if !na.IsAllocated(ingressNetwork) {
		if err := a.allocateNetwork(ctx, nc, ingressNetwork); err != nil {
			log.G(ctx).Errorf("failed allocating ingress network during init: %v", err)
		}

		// Update store after allocation
		if err := a.store.Update(func(tx store.Tx) error {
			if err := store.UpdateNetwork(tx, ingressNetwork); err != nil {
				return err
			}

			return nil
		}); err != nil {
			return fmt.Errorf("failed to create ingress network: %v", err)
		}
	}

	// Allocate networks in the store so far before we started
	// watching.
	a.store.View(func(tx store.ReadTx) {
		networks, err = store.FindNetworks(tx, store.All)
	})
	if err != nil {
		return fmt.Errorf("error listing all networks in store while trying to allocate during init: %v", err)
	}

	for _, n := range networks {
		if na.IsAllocated(n) {
			continue
		}

		if err := a.allocateNetwork(ctx, nc, n); err != nil {
			log.G(ctx).Errorf("failed allocating network %s during init: %v", n.ID, err)
		}
	}

	// Allocate nodes in the store so far before we process watched events.
	var nodes []*api.Node
	a.store.View(func(tx store.ReadTx) {
		nodes, err = store.FindNodes(tx, store.All)
	})
	if err != nil {
		return fmt.Errorf("error listing all services in store while trying to allocate during init: %v", err)
	}

	for _, node := range nodes {
		if na.IsNodeAllocated(node) {
			continue
		}

		if node.Attachment == nil {
			node.Attachment = &api.NetworkAttachment{}
		}

		node.Attachment.Network = ingressNetwork.Copy()
		if err := a.allocateNode(ctx, nc, node); err != nil {
			log.G(ctx).Errorf("Failed to allocate network resources for node %s during init: %v", node.ID, err)
		}
	}

	// Allocate services in the store so far before we process watched events.
	var services []*api.Service
	a.store.View(func(tx store.ReadTx) {
		services, err = store.FindServices(tx, store.All)
	})
	if err != nil {
		return fmt.Errorf("error listing all services in store while trying to allocate during init: %v", err)
	}

	for _, s := range services {
		if s.Spec.Endpoint == nil {
			continue
		}

		if na.IsServiceAllocated(s) {
			continue
		}

		if err := a.allocateService(ctx, nc, s); err != nil {
			log.G(ctx).Errorf("failed allocating service %s during init: %v", s.ID, err)
		}
	}

	// Allocate tasks in the store so far before we started watching.
	var tasks []*api.Task
	a.store.View(func(tx store.ReadTx) {
		tasks, err = store.FindTasks(tx, store.All)
	})
	if err != nil {
		return fmt.Errorf("error listing all tasks in store while trying to allocate during init: %v", err)
	}

	if _, err := a.store.Batch(func(batch *store.Batch) error {
		for _, t := range tasks {
			if taskDead(t) {
				continue
			}

			var s *api.Service
			if t.ServiceID != "" {
				a.store.View(func(tx store.ReadTx) {
					s = store.GetService(tx, t.ServiceID)
				})
			}

			// Populate network attachments in the task
			// based on service spec.
			a.taskCreateNetworkAttachments(t, s)

			if taskReadyForNetworkVote(t, s, nc) {
				if t.Status.State >= api.TaskStateAllocated {
					continue
				}

				if a.taskAllocateVote(networkVoter, t.ID) {
					// If the task is not attached to any network, network
					// allocators job is done. Immediately cast a vote so
					// that the task can be moved to ALLOCATED state as
					// soon as possible.
					if err := batch.Update(func(tx store.Tx) error {
						storeT := store.GetTask(tx, t.ID)
						if storeT == nil {
							return fmt.Errorf("task %s not found while trying to update state", t.ID)
						}

						updateTaskStatus(storeT, api.TaskStateAllocated, "allocated")

						if err := store.UpdateTask(tx, storeT); err != nil {
							return fmt.Errorf("failed updating state in store transaction for task %s: %v", storeT.ID, err)
						}

						return nil
					}); err != nil {
						log.G(ctx).WithError(err).Error("error updating task network")
					}
				}
				continue
			}

			err := batch.Update(func(tx store.Tx) error {
				_, err := a.allocateTask(ctx, nc, tx, t)
				return err
			})
			if err != nil {
				log.G(ctx).Errorf("failed allocating task %s during init: %v", t.ID, err)
				nc.unallocatedTasks[t.ID] = t
			}
		}

		return nil
	}); err != nil {
		return err
	}

	a.netCtx = nc
	return nil
}