Unable to upload VM files to a vSAN datastore

Products

• VMware vSphere ESXi

Issue/Introduction

The following error is seen uploading files to the vSAN datastore through the vSphere Client datastore browser:

"The operation failed for an undetermined reason. Typically this problem occurs due to certificates that the browser does not trust. If you are using self-signed or custom certificates, open the URL below in a new browser tab and accept the certificate, then retry the operation"

Environment

7.0

8.0

Cause

This is due to the web browser not trusting the vCenter certificate and does not indicate a vSAN or storage issue, this error will occur regardless of the underlying storage

Resolution

See the following KB on resolving browser trust issues:

Uploading files through vSphere Client you receive the following error: "The operation failed for an undetermined reason"

Additional Information

VMware does not support using the ESXi host UI client to upload VM files as this results in flat files being stored on the vSAN datastore, rather than the vSAN stream optimized format

While storing flat vmdk files on vSAN can function normally in some circumstances and environment architectures, it's not recommended due to a 255GB vSAN namespace limitation.  The following will be displayed prior to uploading files to the vSAN datastore:

See the following KB for more information:

Flat VMDK on vSAN

 

The only supported method to upload, copy, or create files on vSAN is through the vSphere HTML5 Client datastore browser:

Unable to upload, copy, or create files in a VMware vSAN-backed datastore

Upload Files or Folders to vSAN Datastores