Essential addons
Essential addons are the infrastructure glue every cluster needs to function under SleakOps: networking, autoscaling, and access control. Unlike the optional addons you pick from the Addons list, these five are always present — SleakOps installs them automatically on every managed cluster instead of waiting for you to add them.
They show in the Addons list like any other addon card, with no special badge or visual marker — you recognize them by name and description, not by a distinct treatment.
The five essential addons
| Name | What it does |
|---|---|
| Metrics Server | Collects resource metrics from kubelets and exposes them through the Kubernetes Metrics API, enabling Horizontal Pod Autoscaling and kubectl top. |
| ExternalDNS | Synchronizes exposed Kubernetes Services and Ingresses with DNS providers (Route53), keeping cluster DNS records up to date automatically. |
| Karpenter | A Kubernetes node autoscaler that provisions right-sized compute capacity in response to unschedulable pods, improving efficiency and reducing cost. |
| AWS Auth | Wires SleakOps IAM roles into the cluster's aws-auth ConfigMap and the SleakOps RBAC ClusterRoles, enabling SleakOps integration and role-based access. |
| Load Balancer | The AWS Load Balancer Controller manages Application Load Balancers for Kubernetes Ingresses, plus the public and private IngressClasses used to route external traffic. |
Behavior on imported clusters
On a managed cluster, SleakOps installs and owns all five essential addons. On an imported cluster, SleakOps installs only AWS Auth, automatically, as part of the import; the other four behave differently:
| Addon | On an imported cluster |
|---|---|
| Metrics Server | Not installed automatically. Install it from the Addons list when you need it. |
| ExternalDNS | Not installed automatically. Install it from the Addons list when you need it. |
| Karpenter | Can't be installed: "Karpenter is not supported on imported clusters: node capacity is managed by the cluster owner." |
| Load Balancer | Can't be installed: "The Load Balancer addon is not supported on imported clusters: the ALB controller and its IngressClasses are managed by the cluster owner." SleakOps routes traffic through the IngressClass names set when the cluster was imported. |
On an imported cluster, AWS Auth keeps every entry already in the cluster's aws-auth ConfigMap and adds the SleakOps roles to it.
Restrictions
Configuration — an essential addon's configuration form is read-only on a managed cluster, since SleakOps owns that configuration. Load Balancer is the only essential addon with configurable fields (its public and private IngressClass names), so it's the one where the read-only lock is visible:
Deletion — essential addons can't be deleted on a managed cluster ("'<name>' is an essential addon of this managed cluster and cannot be deleted."): they're only removed when the cluster itself is destroyed. On an imported cluster, they can be deleted like any other addon, unless another addon depends on them.