Virtual Machine displays two datastores in Summary tab despite all its files being located on one datastore

Products

• VMware vCenter Server
• VMware vSphere ESXi

Issue/Introduction

This article provides steps to resolve the issue where a virtual machine displays two datastores where it should only be one as all its files are located in the same datastore.

When all VMware virtual machine files are located in one datastore, you experience these symptoms:

• VM shows on two datastores.
• The Summary tab of the Virtual Machine displays two datastores within the vSphere Web Client.
• The "Datastores and Datastore Clusters" view displays the Virtual Machine in two datastores within the vSphere Web Client.
• The VM is still showing a reference to an old datastore after storage vMotion.

Environment

VMware vSphere ESXi 7.x
VMware vSphere ESXi 8.x

Cause

This issue occurs due to the following:

• The VM is referencing an ISO file and is actively mounted.
• The VM has a serial output configured to a file stored on the datastore. 
• For VMs running on hardware version 10 or older, there is a possibility of the VM referencing a floppy drive. 
• The VM is running on a snapshot and/or a snapshot that might have been taken at a time when the VM had an ISO reference (For example, for older VMs, a floppy drive reference).
• In case of VDI VMs, one of the hard disks attached on the VM could be a delta disk (harddisk-xd-delta.vmdk). This means earlier when the VM was running on the other datastore where there was a snapshot taken and since then it has been running on that snapshot disk.
  • This can be verified by navigating to the datastore holding the vmdk's and then cat the same vmdk file. The 'parentFileNameHint' parameter will show the UUID of the other datastore still showing up on the VM. Also, the file name would be ending with delta.vmdk.

  • esxcli storage vmfs extent list | grep -i Datastore_name
Datastore_name                 xxxxxxxx-xxxxxxxx-744d-xxxxxxxxxxxx              0  naa.600xxxxxxxxxxxxxxxxx          1

    cat harddisk-xd-delta.vmdk
# Disk DescriptorFile
version=1
encoding="UTF-8"
CID=b09d5b6c
parentCID=b09dxxxx
createType="seSparse"
parentFileNameHint="/vmfs/volumes/xxxxxxxx-xxxxxxxx-744d-xxxxxxxxxxxx/datastore/21 Jan 2025 15-45-54.3920Z.vmdk"
# Extent description
RW 209715200 SESPARSE "harddisk-xd-delta-sesparse.vmdk"

Note: In some cases, the vmware.log file of the virtual machine is configured to write to another datastore.

Resolution

To resolve this issue, either do one of the following:

• Consolidate the virtual machine snapshot. For steps and for more information, see Consolidate Snapshots.
• Unmount the ISO file currently mounted to the virtual machine.
• Reconfigure the VM to store the serial output file onto a different datastore. 
• For VMs running on Hardware Version 10 or lower, unmount the floppy drive reference (This would be visible only through the Windows Desktop Client).
• For the VDI VMs still referencing the older datastore and running on the snapshot delta file, we will need to ask the respective VDI vendor to change the hard disk of the VM to not run on a delta disk.

Note: If the ISO file (or floppy drive) is not in use by the virtual machine, select Client Device from the drop-down next to the CD/DVD drive. 

 

vSphere Web Client:

1. Right click the virtual machine and select Edit Settings.
2. Expand the CD/DVD drive, verify if an ISO file is mounted to virtual machine from another datastore.
   
   
3. From the drop-down next to the CD/DVD drive, select Client Device.
   
   
4. Click OK to save the changes to the virtual machine.

 

To address if the vmware.log file of the virtual machine is configured to write to another datastore

1. Navigate to VM Options > Advanced > Edit Configuration:
   
   
   
   
2. Search for the custom field: log.fileName.
3. If the field exist, power off the virtual machine and remove or delete this field.
4. Power on the virtual machine.

If the virtual machine still displays two datastores

Workaround:

A) Compute vMotion the VM to another ESXi host, or re-register the VM:

1. Power off the virtual machine.
2. Remove the virtual machine from the inventory.
3. Re-register the .vmx file. For steps and for more information, see Register an Existing Virtual Machine in the VMware Host Client. 

Workaround:

B) Storage vMotion the VM to the datastore that contains the VM's .vmx file.