Storage related tasks stuck on vCenter for multiple VMs and VMs would go invalid / inaccessible

Products

• VMware vSphere ESXi

Issue/Introduction

Symptoms:

• After triggering the Storage related additional tasks, you may see snapshot, backup and other storage related tasks stuck on vCenter.
• The additional storage IO activity would make VMs to go inaccessible or mark invalid.
• VMs may be restarted by vSphere HA and the restart tasks stuck.

Environment

VMware vSphere ESXi 7.x

VMware vSphere ESXi 8.x

Cause

This would occur when we have QoS enabled on storage devices on external storage which would limit the number of I/Os.

When the QoS is enabled, any additional storage activity would normally restrict the IOps which go beyond the QoS permitted limit.

Resolution

Disable the QoS on storage devices which are enabled with and causing the latency.

Disabling the QoS would allow the clients to perform I/O as expected and reduce the latency.