Snapshot consolidation fails in Virtual Machine with encryption enabled with error "Failed because padding is too short or too long".

Products

• VMware vSphere ESXi

Issue/Introduction

• You are unable to consolidate disks on a Virtual Machine (VM) and receive the error message "Unable to save the snapshot file".
  In the vCenter UI, you see the following specific error:
  "An error occurred while consolidating disks: Unable to save snapshot file. Checkpoint operation not supported for PCI Plugin."
  
  
• The logs in /var/run/log/hostd.log in the host has below entries:
  YYYY-MM-DD <Time> In(166) Hostd[2103533] [Originator@6876 sub=Vmsvc.vm:/vmfs/volumes/<Datastore-UUID>/<VM-name>/<VM-name>.vmx opID=esxui-####-#### sid=######## user=root] State Transition (VM_STATE_ON -> VM_STATE_CONSOLIDATE_ALL_DISKS)
YYYY-MM-DD <Time> Db(167) Hostd[2103535] [Originator@6876 sub=Vigor.Vmsvc.vm:/vmfs/volumes/<Datastore-UUID>/<VM-name>/<VM-name>.vmx] Consolidate Disks message: An error occurred while consolidating disks: Unable to save snapshot file.
YYYY-MM-DD <Time> In(166) Hostd[2103546] [Originator@6876 sub=Vimsvc.ha-eventmgr] Event 133136 : Virtual machine <VM-Name> disks consolidation failed on <ESXI-FQDN> in cluster <ESXI-FQDN> in ha-datacenter.
  
  
• The logs in /vmfs/volumes/datastore-UUID/VM-Name/vmware.log of the VM has below entries:
  YYYY-MM-DD <Time> In(05) vmx md3ax27m-7890307-auto-4p478-h5:70999434-e7-14-4108 SnapshotVMX_Consolidate: Starting online snapshot consolidate operation.
YYYY-MM-DD <Time> In(05) vmx md3ax27m-7890307-auto-4p478-h5:70999434-e7-14-4108 Vix: [mainDispatch.c:4211]: VMAutomation_ReportPowerOpFinished: statevar=3, new AppState=1880, success=1 additionalError=0
YYYY-MM-DD <Time> In(05) vmx md3ax27m-7890307-auto-4p478-h5:70999434-e7-14-4108 Turning on snapshot info cache. VM=<VM-name>.vmx.
YYYY-MM-DD <Time> Er(02) vmx md3ax27m-7890307-auto-4p478-h5:70999434-e7-14-4108 DecryptWithPadding: Failed because padding is too short or too long
YYYY-MM-DD <Time> Er(02) vmx md3ax27m-7890307-auto-4p478-h5:70999434-e7-14-4108 DecryptWithPadding: Failed because padding is too short or too long
YYYY-MM-DD <Time> In(05) vmx md3ax27m-7890307-auto-4p478-h5:70999434-e7-14-4108 DISKLIB-VMFS: "vsan://<UUID>/<VM-ID>" : open successful (1114117) size = 0, hd = 0. Type 20

 

Environment

VMware vSphere ESXI 8.X

Cause

This issue occurs when a VM is encrypted while a backup or snapshot task is in progress, leading to a discrepancy in key-value pairs.

Resolution

To resolve this issue, you must decrypt the affected VM before attempting to consolidate the disks. Follow these steps:

1. Decrypt the VM: Remove the encryption from the virtual machine. This allows the system to resolve padding and key-value pair discrepancies.
2. Run Consolidation: Perform the disk consolidation task. After decryption, the consolidation should complete without the "Unable to save snapshot file" error.
3. Re-encrypt (Optional): Once the consolidation and snapshots are successful, you can re-encrypt the virtual machine.

Additional Information

Decrypt an Encrypted Virtual Machine or Virtual Disk