Taking a snapshot of a virtual machine fails with the error: Error occurred while saving "snapshot_name"

Products

• VMware vSphere ESXi

Issue/Introduction

Symptoms:

• Cannot take a snapshot of the virtual machine
• Taking a snapshot of the virtual machine fails
• The vSphere Client, you see the error:
  
  Error occurred while saving "snapshot_name"

Environment

VMware vSphere ESXi 6.x

VMware vSphere ESXi 7.x

VMware vSphere ESXi 8.x

Cause

This issue occurs if there are any problems with the underlying datastore on which the snapshot is being stored. These datastores can either be NFS or VMFS. VMFS datastores are backed by LUNs accessed through FC/iSCSI/Local SCSI controllers. This error is reported if the ESXi host encounters any storage I/O errors while writing the snapshot to the datastore.

I/O to the datastores can fail for multiple reasons, such as:

• Datastore has reached its maximum capacity.
• I/Os timing out because the underlying storage is overloaded.
• Storage connectivity issues between the ESXi host and storage arrays in case of FC.
• Network connectivity issues between the ESXi host and storage in case of iSCSI and NFS.

Resolution

To resolve this issue, check these options:

• Verify if the I/O errors occur as a result of a transient issue with the underlying storage. Retry the operation and check if it succeeds.
• Ensure that there is sufficient free space on the datastore before attempting the snapshot operation. For more information, see Creating a snapshot for a virtual machine fails with the error: File is larger than maximum file size supported (1012384).
• Resolve storage connectivity issues, if any.
  
  • For Fibre Channel storage, see Troubleshooting fibre channel storage connectivity (1003680)
  • For NFS based storage, see Troubleshooting connectivity issues to an NFS datastore on ESX / ESXi hosts (1003967)

Verify the storage array performance data using the corresponding array management software and resolve issues if the storage array is overloaded.

If the issue persists even after trying these options, file a Support Request with Broadcom Support.

Additional Information

Troubleshooting fibre channel storage connectivity
Troubleshooting connectivity issues to an NFS datastore on ESX and ESXi hosts
Creating a snapshot for an ESXi/ESX virtual machine fails with the error: File is larger than maximum file size supported