> ## Documentation Index > Fetch the complete documentation index at: https://docs.firebolt.io/llms.txt > Use this file to discover all available pages before exploring further. # ClusterFireboltEngineClass CRD reference > Spec and SKU-only template fields for ClusterFireboltEngineClass. ## Spec reference `ClusterFireboltEngineClass` is a cluster-scoped SKU catalog. Engines select it by name through `spec.engineClassRef`. The Firebolt Operator resolves that name namespaced-first: a [`FireboltEngineClass`](./fireboltengineclass-crd-reference) in the Engine's namespace if present, otherwise this cluster object. The catalog carries only `spec.template`. Namespaced references (ServiceAccount name, Secret refs, IAM annotations, ConfigMap refs, `persistentVolumeClaim` volumes, resource claims) and non-template Engine settings (`storage`, `customEngineConfig`, `rollout`, `drainCheckEnabled`, `drainCheckInterval`, `autoStop`, `uiSidecar`) stay on [`FireboltEnginePreset`](./fireboltenginepreset-crd-reference), [`FireboltEngineClass`](./fireboltengineclass-crd-reference), or the Engine spec. The operator does not reconcile this object. Cluster admins or a cell manager author it; Engine reconcilers consume it read-only. | Field | Required | Default | Description | | --------------- | -------- | ------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `spec.template` | **Yes** | – | [`PodTemplateSpec`](https://kubernetes.io/docs/reference/kubernetes-api/workload-resources/pod-template-v1/) merged under each Engine that resolves this catalog object. See [SKU-only fields](#sku-only-fields) and [EngineClass configuration inheritance](../engineclass/configuration-inheritance). | A catalog edit to `spec.template` reshapes the rendered engine pod, so it rolls a new blue-green generation on every Engine that resolved to this object. ## SKU-only fields The validating webhook and the Engine resolver reject every namespaced reference on `spec.template`. A cluster-scoped object has no namespace of its own, so such a name would bind to whatever happens to exist in each consuming namespace, and the same catalog entry would render differently per namespace, or not at all: | Path | Allowed | Notes | | ---------------------------------------------------------------- | ------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `spec.template.spec.nodeSelector` | Yes | Instance type / family. | | `spec.template.spec.tolerations` | Yes | Node taints for the SKU pool. | | `spec.template.spec.affinity` | Yes | SKU placement. | | `spec.template.spec.initContainers` | Yes | Node setup. Secret and ConfigMap env, and Secret, ConfigMap, and claim volumes, are rejected. | | `spec.template.spec.containers[name=="engine"].image` | Yes | Optional default engine image. | | `spec.template.spec.containers[name=="engine"].resources` | Yes | SKU resource requests and limits. | | `spec.template.spec.serviceAccountName` | No | Belongs on FireboltEnginePreset. | | `spec.template.spec.imagePullSecrets` | No | Namespace-resolved Secret names. | | `spec.template.metadata.annotations[iam.amazonaws.com/role]` | No | kube2iam / kiam identity. | | `spec.template.metadata.annotations[eks.amazonaws.com/role-arn]` | No | IRSA identity. | | Secret volumes and Secret env | No | Credential material is namespaced. | | ConfigMap volumes and ConfigMap env | No | The name would resolve per consuming namespace. Put shared engine settings on `customEngineConfig`, or the ConfigMap ref on the namespaced class or Preset. | | `persistentVolumeClaim` volumes | No | A claim exists in one namespace. `emptyDir`, `downwardAPI`, and `ephemeral` claim templates stay allowed, because they name nothing namespaced. | | `dataSource` or `dataSourceRef` on an `ephemeral` claim template | No | Both seed the new claim from a claim or snapshot resolved in the consuming namespace, and `dataSourceRef` can name one in a third namespace. Every other claim-template field (`storageClassName`, `volumeAttributesClassName`, `volumeName`) names a cluster-scoped object and stays allowed. | | `spec.template.spec.resourceClaims` | No | `resourceClaimName` and `resourceClaimTemplateName` both name a namespaced dynamic-resource-allocation object. | | `resources.claims` on any container | No | A container claim can only be satisfied by a `spec.template.spec.resourceClaims` entry, which the catalog cannot carry. | Firebolt Operator-owned paths on the template are the same as [`FireboltEngineClass.spec.template`](./fireboltengineclass-crd-reference#firebolt-operator-owned-fields-on-class-templates). Short name: `cfirengc`. ```bash theme={"theme":{"light":"css-variables","dark":"css-variables"}} kubectl get cfirengc ``` ``` NAME AGE s-amd-co 24h ``` ## Deletion Catalog delete is allowed. Engines that still name the object emit a Warning `EngineClassNotFound` Event, keep the last applied pods, and retry until the SKU is restored or `spec.engineClassRef` is cleared or overridden by a namespaced `FireboltEngineClass` of the same name.