Taking a quiesce snapshot of Windows VM causes the event 15: The device, \Device\HarddiskX\DRXX, is not ready for access yet.

Products

• VMware vSphere ESXi

Issue/Introduction

Symptoms:

• The Event log of the Windows virtual machine guest operating system shows the error:

Event Type: Error
Event Source: Disk
Event Category: None
Event ID: 15
Date: 7/8/2021
Time: 3:33:08 AM
User: N/A
Computer: VMname
Description:
The device, \Device\Harddisk3\DR9, is not ready for access yet.

• The snapshot task completes with success.
• Event ID 15, occurs after the Event ID 157.

• In the vmware.log, you see log entries similar to:

[YYYY-MM-DDTHH:MM:SS]| vcpu-2| I125: ToolsBackup: hot removing disk VMname.vmdk from node scsi0:3.
[YYYY-MM-DDTHH:MM:SS]| vcpu-2| I125: ToolsBackup: hot removing disk VMname.vmdk from node scsi0:2.

Notes:
The preceding log excerpts are only examples. Date, time, and environmental variables may vary depending on your environment.

Environment

VMware vSphere ESXi 8.x

VMware vSphere ESXi 7.x
VMware vSphere ESXi 6.x

Cause

In current design of "VMware Snapshot Provider", the snapshot disks are hot-removed without prompt notification to the Windows OS, this will cause the device to be unexpectedly removed without notifying the guest OS, which causes the device to not be accessible (event 15).

When quiesced snapshot process begin, VMware snapshot provider hot-adds the writable snapshot disks (shadow copy volume disks); When quiesced snapshot process ends, VMware snapshot provider hot-removes the writable snapshot disks (shadow copy volume disks), then event15 is generated for "writable snapshot disk" because the writable snapshot disks are removed forcibly from Windows perspective.

Resolution

This issue is fixed in VMtools version 12.3.0

Workaround:
None. The Event ID 15 and Event ID 157 can be safety ignored after taking a quiescing snapshot.

Additional Information

Impact/Risks:
None.

For VSS snapshot process, the snapshot disk data is consistent when it comes to the stage of hot-removing snapshot disks. The event error is benign and can be safely ignored.