Not able to consolidate a VM due to insufficient disk space on datastore.

Products

• VMware vSphere ESXi

Issue/Introduction

• You are unable to consolidate a VM snapshot.
• The reason for this is the message:
  Insufficient disk space on datastore '<datastore name>'. Consolidation failed for disk node 'scsi0:1': There is not enough space on the file system for the selected operation. An error occurred while consolidating disks: There is not enough space on the file system for the selected operation.

Environment

VMware vSphere ESXi (All Versions)

Cause

In order to consolidate a snapshot chain, the ESXi host must have sufficient free disk space on the virtual machine's assigned datastore. This space is used to ensure the consolidation properly written to the base disk.  See KB316575 for more details.

Resolution

Multiple options exist, depending on the environment and hardware configurations:

1. Expand the LUN to at least the recommended size required by the error message details.
2. Storage vMotion the virtual machine disks to another LUN with more available freespace.
3. Clone the virtual machine to a new VM on a new datastore. This will consolidate the snapshots during the operation. Delete the original VM once the new VM is deemed up and operational.

Additional information on errors when consolidating snapshots can be found in the following KB. Errors Consolidating Snapshots