vSAN Proactive Test - VM Creation Test - Displays error "Unable to run VM Creation Test. Try again later."

Products

• VMware vSAN

Issue/Introduction

Symptoms:

• vSAN Proactive Test for VM creation works, but takes a long time and displays the error - "Unable to run VM Creation Test. Try again later.". This test is found in location: vSphere Client > vSAN Cluster > Monitor > vSAN - Proactive Tests > VM Creation Test.
  
• VM creation/cloning on vSAN datastore works, but it takes a very long time.

Environment

VMware vSAN 8.x

Cause

• The test appears to fail as the VM creation took a very long time to complete.

• Manual creation/cloning of small sized VM (<100GB) would also take a long time, indicating an underlying performance issue on the vSAN cluster.

Resolution

• Performance issue on the vSAN cluster can be caused due to various reasons:

  • Incorrect driver/firmware combination for the HBAs used for vSAN disks/devices. If they are incorrect, they need to be upgraded to the supported versions. Determining Network/Storage firmware and driver version in ESXi.

  • Deteriorating/faulty physical disks which back vSAN.

  • Unsupported hardware used for vSAN.

• If the cause of the issue cannot be identified and fixed, open a case with Broadcom Technical Support to investigate this further.