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Centralized delegate approach

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In the centralized delegate approach, one Harness Delegate runs on a central infrastructure and orchestrates chaos experiments against multiple target clusters through Kubernetes connectors. The Delegate itself does not need to live in the target cluster; instead, the Kubernetes connector's service account holds the chaos permissions.

This is the right pattern when a platform team owns the Delegate and many product teams contribute clusters to test against.

Centralized Delegate communicating with target clusters

Before you begin​

  • The Harness Delegate is already installed on a central infrastructure (a hub cluster, a management cluster, or any infrastructure with reachability to the target). Go to Install Delegate if it is not.
  • Standard Delegate image. If you are pinned to the minimal Delegate image, you need to install kubectl and go-template first. Go to Using the minimal Delegate image for the two install options.
  • Network connectivity between the central infrastructure and every target cluster the Delegate will inject chaos into.
  • kubectl access to the target cluster.
  • A Harness environment to attach the infrastructure to. Go to Create an environment if you do not have one.

Step 1. Create the service account and chaos RBAC on the target cluster​

On the target cluster, apply the Centralized delegate approach (Delegate outside target cluster) manifest set from Cluster permissions → Example RBAC manifests. The set contains:

  1. A ServiceAccount (chaos-sa) and a long-lived token Secret in a dedicated namespace (harness-delegate-chaos).
  2. A namespace Role and RoleBinding so the Delegate can manage chaos runner pods inside that namespace.
  3. A ClusterRole (chaos-clusterrole) with the discovery and chaos permissions the runner needs.
  4. Either a ClusterRoleBinding (chaos can target any namespace) or per-namespace RoleBindings (chaos can target only onboarded namespaces).
Keep namespaces consistent

Harness recommends keeping the Delegate namespace, the chaos infrastructure namespace, and the service account namespace identical (harness-delegate-chaos in the example). This avoids cross-namespace RBAC surprises.

Pick a binding mode
  • Bind to all namespaces with a ClusterRoleBinding. Easier to manage; less precise.
  • Bind to specific namespaces with one RoleBinding per application namespace. Explicit per-app onboarding.

Generate the service account token​

Fetch the bound token; you will paste it into the Kubernetes connector in the next step.

kubectl -n harness-delegate-chaos get secret chaos-sa-secret \
  -o jsonpath='{.data.token}' | base64 --decode

Step 2. Create the Kubernetes connector​

In Harness, create a Kubernetes Direct Connection connector that authenticates with the service account token from Step 1.

  • Master URL: run kubectl cluster-info on the target cluster and copy the control plane URL.
  • Service account token: the base64-decoded value from Step 1.

Kubernetes connector using service-account-token authentication

Step 3. Create the Harness infrastructure definition​

In Harness, create the chaos infrastructure using the connector from Step 2. Use the Kubernetes (Harness Infrastructure) tab under Resilience Testing → Project Settings → Resilience Testing Infrastructures. The form fields are identical to the dedicated delegate Basic install.

Step 4. Edit the infrastructure to use the chaos namespace and service account​

After enabling chaos on the infrastructure, open it and edit it so the chaos runner is launched in harness-delegate-chaos (or the namespace you used) with chaos-sa as the service account. This ensures experiments run with the bindings from Step 1.

Service account configured on the infrastructure

Next steps​

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