NSM On-Prem KVM disk check

NSM on-Prem deployments on the KVM platform could face issues with update if the VM disk attached is a VirtIO disk. This article helps with the steps to check if a disk used by the VM is a Virtio disk.

• Open the virt-viewer for NSM on-Prem VM. Click on the "Details" tab.
  
• Among the list of Virtual Machine Hardware in use, look for hardware of type “Disk”.
  
• If the disk is attached to a SCSI bus or IDE. You can proceed with NSM update.
  
• If the disk attached is on “Disk bus” : VirtIO, please follow below steps.
  

The following steps will re-attach the NSM on-prem disk image on the 'SCSI' bus. The process should not lead to any data loss. For extra caution, Create a Scheduled Backup, and export addUnit json and settings before proceeding.

1. Shut down the NSM on-Prem VM.
2. In the VM details tab. Take note of the Virtual Disk “Source path” details.
   
3. Remove the VirtIO disk by selecting the disk and pressing the “Remove” button. This only removes the virtual hardware which attaches a disk over an emulated bus, do not delete the virtual disk file.
   
   Make sure you leave the option to “Delete associated storage files” unchecked and click on the “Delete” button.
   
4. Add the detached virtual disk back to the VM, but this time configure virtual storage hardware on the SCSI bus. Click “Add Hardware”, and choose Storage.
   
   
   
5. Click on “Manage…” and choose the same Virtual Disk as noted in Step 2 and click on “Choose Volume”
   
6. Choose SCSI from the “Bus Type” dropdown menu. Click on “Finish” to add the virtual disk back to the VM.
   
   
   
7. Start the VM and proceed with the update.