# VirtualNode

VirtualNode represents a newly defined AppMesh VirtualNode.

Any inbound traffic that your virtual node expects should be specified as a
listener. Any outbound traffic that your virtual node expects to reach
should be specified as a backend.
[disable-awslint:no-grants]

Extends: Construct › Resource › VirtualNode
Implements: IResource, IVirtualNode, IEnvironmentAware, IVirtualNodeRef, IConstruct, IDependable

- CloudFormation: [`AWS::AppMesh::VirtualNode`](https://docs.aws.amazon.com/AWSCloudFormation/latest/TemplateReference/aws-resource-appmesh-virtualnode.html)
- L1 type: [`CfnVirtualNode`](/cdk/api/v2/docs/aws-cdk-lib.aws_appmesh.CfnVirtualNode.html)
- Source: [`aws-appmesh/lib/virtual-node.ts`](https://github.com/aws/aws-cdk/blob/v2.274.0/packages/aws-cdk-lib/aws-appmesh/lib/virtual-node.ts#L158)
- Type last changed: v2.229.0 · 24 Nov 2025

## Example

```ts
// Cloud Map service discovery is currently required for host ejection by outlier detection
const vpc = new ec2.Vpc(this, 'vpc');
const namespace = new cloudmap.PrivateDnsNamespace(this, 'test-namespace', {
    vpc,
    name: 'domain.local',
});
const service = namespace.createService('Svc');

declare const mesh: appmesh.Mesh;
const node = mesh.addVirtualNode('virtual-node', {
  serviceDiscovery: appmesh.ServiceDiscovery.cloudMap(service),
  listeners: [appmesh.VirtualNodeListener.http({
    outlierDetection: {
      baseEjectionDuration: Duration.seconds(10),
      interval: Duration.seconds(30),
      maxEjectionPercent: 50,
      maxServerErrors: 5,
    },
  })],
});
```

## Initializer

```ts
new VirtualNode(scope: Construct, id: string, props: VirtualNodeProps)
```

## Construct Props

- `accessLog`: [AccessLog](/cdk/api/v2/docs/aws-cdk-lib.aws_appmesh.AccessLog.html) — Access Logging Configuration for the virtual node.

  **Default:** No access logging

- `backendDefaults`: [BackendDefaults](/cdk/api/v2/docs/aws-cdk-lib.aws_appmesh.BackendDefaults.html) — Default Configuration Virtual Node uses to communicate with Virtual Service.

  **Default:** No Config

- `backends`: [Backend](/cdk/api/v2/docs/aws-cdk-lib.aws_appmesh.Backend.html)[] — Virtual Services that this is node expected to send outbound traffic to.

  **Default:** No backends

- `listeners`: [VirtualNodeListener](/cdk/api/v2/docs/aws-cdk-lib.aws_appmesh.VirtualNodeListener.html)[] — Initial listener for the virtual node.

  **Default:** No listeners

- `mesh`: [IMesh](/cdk/api/v2/docs/aws-cdk-lib.aws_appmesh.IMesh.html) (required) — The Mesh which the VirtualNode belongs to.

- `serviceDiscovery`: [ServiceDiscovery](/cdk/api/v2/docs/aws-cdk-lib.aws_appmesh.ServiceDiscovery.html) — Defines how upstream clients will discover this VirtualNode.

  **Default:** No Service Discovery

- `virtualNodeName`: string — The name of the VirtualNode.

  **Default:** A name is automatically determined

## Properties

- `env`: [ResourceEnvironment](/cdk/api/v2/docs/aws-cdk-lib.interfaces.ResourceEnvironment.html) (required) — The environment this resource belongs to.

  For resources that are created and managed in a Stack (those created by
  creating new class instances like `new Role()`, `new Bucket()`, etc.), this
  is always the same as the environment of the stack they belong to.

  For referenced resources (those obtained from referencing methods like
  `Role.fromRoleArn()`, `Bucket.fromBucketName()`, etc.), they might be
  different than the stack they were imported into.

- `grants`: [VirtualNodeGrants](/cdk/api/v2/docs/aws-cdk-lib.aws_appmesh.VirtualNodeGrants.html) (required) — Collection of grants for this Virtual Node.

- `mesh`: [IMesh](/cdk/api/v2/docs/aws-cdk-lib.aws_appmesh.IMesh.html) (required) — The Mesh which the VirtualNode belongs to.

- `node`: [Node](/cdk/api/v2/docs/constructs.Node.html) (required) — The tree node.

- `PROPERTY_INJECTION_ID`: string (required) (static) — Uniquely identifies this class.

- `stack`: [Stack](/cdk/api/v2/docs/aws-cdk-lib.Stack.html) (required) — The stack in which this resource is defined.

- `virtualNodeArn`: string (required) — The Amazon Resource Name belonging to the VirtualNode.

- `virtualNodeName`: string (required) — The name of the VirtualNode.

- `virtualNodeRef`: [VirtualNodeReference](/cdk/api/v2/docs/aws-cdk-lib.interfaces.aws_appmesh.VirtualNodeReference.html) (required) — A reference to a VirtualNode resource.

## Methods

- `addBackend(backend: Backend): void` — Add a Virtual Services that this node is expected to send outbound traffic to.

- `addListener(listener: VirtualNodeListener): void` — Utility method to add an inbound listener for this VirtualNode.

  Note: At this time, Virtual Nodes support at most one listener. Adding
  more than one will result in a failure to deploy the CloudFormation stack.
  However, the App Mesh team has plans to add support for multiple listeners
  on Virtual Nodes and Virtual Routers.

- `applyCrossStackReferenceStrength(strength: ReferenceStrength): void` — Override the cross-stack reference strength for this resource.

  When set, any cross-stack reference to this resource will use the specified
  mechanism instead of the global default determined by the
  `@aws-cdk/core:defaultCrossStackReferences` context key. This is useful for
  selectively weakening specific references to avoid the "deadly embrace" problem
  without changing the app-wide default.

  **Parameters**

  - `strength` — - The reference strength to use for this resource.

- `applyRemovalPolicy(policy: RemovalPolicy): void` — Apply the given removal policy to this resource.

  The Removal Policy controls what happens to this resource when it stops
  being managed by CloudFormation, either because you've removed it from the
  CDK application or because you've made a change that requires the resource
  to be replaced.

  The resource can be deleted (`RemovalPolicy.DESTROY`), or left in your AWS
  account for data recovery and cleanup later (`RemovalPolicy.RETAIN`).

- `fromVirtualNodeArn(scope: Construct, id: string, virtualNodeArn: string): IVirtualNode` (static) — Import an existing VirtualNode given an ARN.

- `fromVirtualNodeAttributes(scope: Construct, id: string, attrs: VirtualNodeAttributes): IVirtualNode` (static) — Import an existing VirtualNode given its name.

- `grantStreamAggregatedResources(identity: IGrantable): Grant` — The use of this method is discouraged. Please use `grants.streamAggregatedResources()` instead.

  [disable-awslint:no-grants]

- `isConstruct(x: any): boolean` (static) — Checks if `x` is a construct.

  Use this method instead of `instanceof` to properly detect `Construct`
  instances, even when the construct library is symlinked.

  Explanation: in JavaScript, multiple copies of the `constructs` library on
  disk are seen as independent, completely different libraries. As a
  consequence, the class `Construct` in each copy of the `constructs` library
  is seen as a different class, and an instance of one class will not test as
  `instanceof` the other class. `npm install` will not create installations
  like this, but users may manually symlink construct libraries together or
  use a monorepo tool: in those cases, multiple copies of the `constructs`
  library can be accidentally installed, and `instanceof` will behave
  unpredictably. It is safest to avoid using `instanceof`, and using
  this type-testing method instead.

  **Parameters**

  - `x` — Any object.

  **Returns:** true if `x` is an object created from a class which extends `Construct`.

- `isOwnedResource(construct: IConstruct): boolean` (static) — Returns true if the construct was created by CDK, and false otherwise.

- `isResource(construct: IConstruct): boolean` (static) — Check whether the given construct is a Resource.

- `toString(): string` — Returns a string representation of this construct.

- `with(...mixins: IMixin[]): IConstruct` — Applies one or more mixins to this construct.

  Mixins are applied in order. The list of constructs is captured at the
  start of the call, so constructs added by a mixin will not be visited.
  Use multiple `with()` calls if subsequent mixins should apply to added
  constructs.