--- title: Workload Group description: Describes a collection of workload instances. location: https://istio.io/docs/reference/config/networking/workload-group.html layout: protoc-gen-docs generator: protoc-gen-docs schema: istio.networking.v1alpha3.WorkloadGroup aliases: [/docs/reference/config/networking/v1alpha3/workload-group] number_of_entries: 7 ---

`WorkloadGroup` describes a collection of workload instances. It provides a specification that the workload instances can use to bootstrap their proxies, including the metadata and identity. It is only intended to be used with non-k8s workloads like Virtual Machines, and is meant to mimic the existing sidecar injection and deployment specification model used for Kubernetes workloads to bootstrap Istio proxies.

The following example declares a workload group representing a collection of workloads that will be registered under `reviews` in namespace `bookinfo`. The set of labels will be associated with each workload instance during the bootstrap process, and the ports 3550 and 8080 will be associated with the workload group and use service account `default`. `app.kubernetes.io/version` is just an arbitrary example of a label.

    apiVersion: networking.istio.io/v1
    kind: WorkloadGroup
    metadata:
      name: reviews
      namespace: bookinfo
    spec:
      metadata:
        labels:
          app.kubernetes.io/name: reviews
          app.kubernetes.io/version: "1.3.4"
      template:
        ports:
          grpc: 3550
          http: 8080
        serviceAccount: default
      probe:
        initialDelaySeconds: 5
        timeoutSeconds: 3
        periodSeconds: 4
        successThreshold: 3
        failureThreshold: 3
        httpGet:
         path: /foo/bar
         host: 127.0.0.1
         port: 3100
         scheme: HTTPS
         httpHeaders:
         - name: Lit-Header
           value: Im-The-Best

## WorkloadGroup

`WorkloadGroup` enables specifying the properties of a single workload for bootstrap and provides a template for `WorkloadEntry`, similar to how `Deployment` specifies properties of workloads via `Pod` templates. A `WorkloadGroup` can have more than one `WorkloadEntry`. `WorkloadGroup` has no relationship to resources which control service registry like `ServiceEntry` and as such doesn’t configure host name for these workloads.

Field | Type | Description | Required
--- | --- | --- | ---
`metadata` | `ObjectMeta` | Metadata that will be used for all corresponding `WorkloadEntries`. User labels for a workload group should be set here in `metadata` rather than in `template`. | No
`template` | `WorkloadEntry` | Template to be used for the generation of `WorkloadEntry` resources that belong to this `WorkloadGroup`. Please note that `address` and `labels` fields should not be set in the template, and an empty `serviceAccount` should default to `default`. The workload identities (mTLS certificates) will be bootstrapped using the specified service account’s token. Workload entries in this group will be in the same namespace as the workload group, and inherit the labels and annotations from the above `metadata` field. | Yes
`probe` | `ReadinessProbe` | `ReadinessProbe` describes the configuration the user must provide for healthchecking on their workload. This configuration mirrors K8S in both syntax and logic for the most part. | No

## ReadinessProbe

Field | Type | Description | Required
--- | --- | --- | ---
`initialDelaySeconds` | `int32` | Number of seconds after the container has started before readiness probes are initiated. | No
`timeoutSeconds` | `int32` | Number of seconds after which the probe times out. Defaults to 1 second. Minimum value is 1 second. | No
`periodSeconds` | `int32` | How often (in seconds) to perform the probe. Default to 10 seconds. Minimum value is 1 second. | No
`successThreshold` | `int32` | Minimum consecutive successes for the probe to be considered successful after having failed. Defaults to 1 second. | No
`failureThreshold` | `int32` | Minimum consecutive failures for the probe to be considered failed after having succeeded. Defaults to 3 seconds. | No
`httpGet` | `HTTPHealthCheckConfig (oneof)` | `httpGet` is performed to a given endpoint and the status/able to connect determines health. | No
`tcpSocket` | `TCPHealthCheckConfig (oneof)` | Health is determined by if the proxy is able to connect. | No
`exec` | `ExecHealthCheckConfig (oneof)` | Health is determined by how the command that is executed exited. | No

## HTTPHealthCheckConfig

Field | Type | Description | Required
--- | --- | --- | ---
`path` | `string` | Path to access on the HTTP server. | No
`port` | `uint32` | Port on which the endpoint lives. | Yes
`host` | `string` | Host name to connect to, defaults to the pod IP. You probably want to set “Host” in httpHeaders instead. | No
`scheme` | `string` | HTTP or HTTPS, defaults to HTTP | No
`httpHeaders` | `HTTPHeader[]` | Headers the proxy will pass on to make the request. Allows repeated headers. | No

## HTTPHeader

Field | Type | Description | Required
--- | --- | --- | ---
`name` | `string` | The header field name | No
`value` | `string` | The header field value | No

## TCPHealthCheckConfig

Field | Type | Description | Required
--- | --- | --- | ---
`host` | `string` | Host to connect to, defaults to localhost | No
`port` | `uint32` | Port of host | Yes

## ExecHealthCheckConfig

Field | Type | Description | Required
--- | --- | --- | ---
`command` | `string[]` | Command to run. Exit status of 0 is treated as live/healthy and non-zero is unhealthy. | No

## WorkloadGroup.ObjectMeta

`ObjectMeta` describes metadata that will be attached to a `WorkloadEntry`. It is a subset of the supported Kubernetes metadata.

Field | Type | Description | Required
--- | --- | --- | ---
`labels` | `map<string, string>` | Labels to attach | No
`annotations` | `map<string, string>` | Annotations to attach | No