n2-custom Instance Types Not Discovered by Karpenter GCP Provider #144
Description
GitHub Issue: n2-custom Instance Types Not Discovered by Karpenter GCP Provider
What happened:
Karpenter GCP provider fails to discover n2-custom instance types, specifically n2-custom-8-24576, even though these instance types are:
✅ Available and running successfully in the cluster (8 nodes currently running n2-custom-8-24576)
✅ Located in the same zone (europe-west1-b) where Karpenter is configured
✅ Working with GKE's native autoscaler
❌ Not discovered by Karpenter's instance type discovery
Error logs:
{"level":"INFO","time":"2025-10-23T08:52:39.549Z","logger":"controller","message":"skipping, nodepool requirements filtered out all instance types","commit":"ab4fd3d","controller":"provisioner","namespace":"","name":"","reconcileID":"4ab7a186-bd2d-400c-b1b2-80ed4df090fc","NodePool":{"name":"custom-nodepool"}}
What you expected to happen:
-
Karpenter should be able to discover and provision n2-custom-8-24576 instance types since they are:
-
Available in the target zone (europe-west1-b)
-
Successfully running in the cluster
-
Compatible with the cluster configuration
How to reproduce it (as minimally and precisely as possible):
- Create a GKE cluster with existing n2-custom-8-24576 nodes in europe-west1-b zone
- Install Karpenter GCP provider using the official chart
- Create a NodePool with the following configuration:
apiVersion: karpenter.sh/v1 kind: NodePool metadata: name: custom-nodepool spec: weight: 10 template: spec: nodeClassRef: name: default-example kind: GCENodeClass group: karpenter.k8s.gcp requirements: - key: "karpenter.sh/capacity-type" operator: In values: ["on-demand", "spot"] - key: "karpenter.k8s.gcp/instance-family" operator: In values: ["n2-custom"] - key: "node.kubernetes.io/instance-type" operator: In values: ["n2-custom-8-24576"] - key: "kubernetes.io/arch" operator: In values: ["amd64"] - key: "topology.kubernetes.io/zone" operator: In values: ["europe-west1-b"] taints: - key: spot-standard value: "true" effect: NoSchedule
Deploy a test workload that requires node provisioning
Observe that Karpenter logs show "skipping, nodepool requirements filtered out all instance types"
Anything else we need to know?:
Working Alternative: Karpenter successfully provisions n1-standard-4 instances in the same zone
Instance Type Discovery: Karpenter discovered 422 instance types but n2-custom family is not included
GKE Compatibility: n2-custom-8-24576 works perfectly with GKE's native autoscaler
Zone Confirmation: All existing n2-custom-8-24576 nodes are in europe-west1-b zone
Environment:
Karpenter-provider-gcp version: v0.0.1 (image: public.ecr.aws/cloudpilotai/gcp/karpenter:v0.0.1)
GKE version: v1.33.5-gke.1080000
Cluster: dsa-browser-farm-1-dev
Zone: europe-west1-b
Project: dsa-acq-gke-dev
Karpenter Namespace: karpenter-system
NodePool Status: Shows NoCompatibleInstanceTypes warning