When creating an AWS HyperShift cluster with ARM64 architecture, the NodePool creation fails during CRD validation with the following error:
NodePool.hypershift.openshift.io "939ae839d0524c0822c8-us-east-1a" is invalid:
spec: Invalid value: "object": no such key: imageType evaluating rule:
ImageType 'Windows' requires arch 'amd64' (AWS only)
The root cause is a CEL validation rule in {{api/hypershift/v1beta1/nodepool_types.go:103}} that attempts to access the optional {{imageType}} field without first checking if it exists. 

    

Introduced in PR #6746 (commit fd07723d4), merged November 5, 2025

    

always
    

1. Ensure you have a cluster with the NodePool CRD from commit fd07723d4 or later
2. Attempt to create an AWS cluster with ARM64 architecture:
{code:bash}
hypershift create cluster aws \
  --name test-cluster \
  --node-pool-replicas 2 \
  --instance-type m6g.xlarge \
  --region us-east-1 \
  --zones us-east-1a \
  --arch=arm64 \
  --base-domain example.com \
  [... other required flags ...]
3. Observe the NodePool creation failure with the "no such key: imageType" error

    

* NodePool creation is blocked
* Error message: "no such key: imageType evaluating rule: ImageType 'Windows' requires arch 'amd64' (AWS only)"
    

* NodePool is created
* Hostedcluster is created successfully