Error received “Parameters for device 'scsi1' may not be modified while the virtual machine is powered on” when deploying a VM with multiple disks via vRealize Automation

Products

• VMware vCenter Server
• VMware vSphere ESXi

Issue/Introduction

• When deploying a virtual machine through vRealize Automation, the following error appears during provisioning when multiple disks are being attached : 
  

  "Failed to manage disks for virtual machine 'VM_Name' with exception : ("Parameters for device 'scsi1' may not be modified while the virtual machine is powered on.", None)"

• The issue only occurs during the automated deployment process and when multiple disks are provisioned during deployment. Adding disks manually to the same VM through vCenter Server works successfully. 
• There is a template from which the VM is deployed which is provided to the automation tool. 

Environment

VMware vCenter Server 

VMware vSphere ESXi 

Cause

This issue occurs if there is a pre-configured secondary SCSI controller (scsi1) set to one of the Storage controllers. When Automation tool attempted to add additional virtual disks, it tried to modify parameters of the pre-existing SCSI controller on a powered-on VM, which is not allowed.

Resolution

1. Modify the template from where the VM is getting deployed to remove the additional SCSI controller and ensure that only one default SCSI controller is present i.e. scsi0. 
   NOTE: In the above example, the additional SCSI Controller was configured as LSI Logic SAS. 
2. Redeploy the VM from vRealize Automation using the updated template. The playbook on the automation tool should now be able to attach disks dynamically without encountering the SCSI controller modification error.