Error: “Internal Server Error – NoDiskSpace fault during vApp recompose” in VMware Cloud Director UI

Products

• VMware Cloud Director

Issue/Introduction

• When attempting to recompose a vApp or modify a virtual machine’s compute policy, VMware Cloud Director displays the following error in the UI:
  
  Internal Server Error
com.vmware.vim.binding.vim.fault.NoDiskSpace cannot be cast to class
com.vmware.vcloud.api.presentation.service.PersonaAwareException


• The error occurs shortly after initiating a recompose task, even when the change involves only CPU or memory modifications.
  
  
• In vCenter, the corresponding task shows Clone virtual machine or Relocate virtual machine failing with Insufficient disk space on datastore.
  
  
• The vApp task in VMware Cloud Director then fails and rolls back.

Environment

VMware Cloud Director 10.6.1.1
vCenter Server 8.x

Cause

This issue can occur when the datastore(s) assigned to the target storage policy do not have enough free capacity to accommodate the clone or relocation task initiated by VCD.

During a vApp recompose, VMware Cloud Director validates VM storage and compute policies. If the existing datastore does not match the desired storage policy, VCD triggers a CloneVM_Task or RelocateVM_Task in vCenter to bring the VM into compliance.

vCenter returns a vim.fault.NoDiskSpace error when the datastore lacks sufficient capacity for the operation.

VCD then attempts to wrap this vCenter error, resulting in a generic “Internal Server Error” message in the UI.

Resolution

Perform the following validation and corrective steps in vCenter and VCD:

1. Check datastore capacity in vCenter
   
   Navigate to the datastore(s) linked to the storage policy in question.
   Verify there is enough free space to accommodate the full provisioned size of the VM.
   For large VMs (multi-TB disks), ensure free capacity ≥ provisioned size + approx. 20% buffer.
   
   
2. Verify datastore accessibility
   
   Confirm the datastore is mounted on all ESXi hosts participating in the target cluster or resource pool.
   Unmounted or inaccessible datastores can cause NoDiskSpace or compliance errors.
   
   
3. Validate storage policy mapping
   
   In vCenter >Home Menu> Policies and Profiles > VM Storage Policies
   
   Confirm the target policy lists the correct datastores as Compatible.
   
   
   
4. Check for locked or open snapshots
   
   In VCD > Tenant Portal > vApps > Snapshots.
   
   Consolidate any active snapshots in VCD prior to retrying the task.
   
   
5. Temporarily suspend replication or backup operations that may lock the VM’s disks.
   
   VCDA > Replications > Incoming Replications / Outgoing Replications > All Actions
   
   
6. Retry the recompose or compute change
   
   Once datastore capacity and accessibility are confirmed, retry the operation in VCD.
   
   

Note** Large VMs may take 1–2 hours to complete due to full disk copy operations during clone or relocate.