Virtual Machine Fails to Detect Boot Device and Defaults to Network Boot

Products

• VMware vSphere ESXi

Issue/Introduction

1. The virtual machine powers on but does not load the operating system. Instead of detecting its primary disk, it falls back to “Network boot from VMware VMXNET3.”
   
   
2. While the same VMDK is attached to another test VM, the boot device is still not detected, and the OS fails to load.

Environment

7.0.x

Cause

The primary VMDK is unable to provide any valid boot information. This typically happens when the disk is corrupted or the operating system files on it are no longer accessible, causing the VM to skip the local disk and attempt a network boot.

Resolution

Reimage the virtual machine with a fresh operating system. This ensures the VM starts with a healthy OS and resolves the boot device detection issue.

Note: You can also attach the disks as existing, and if there are any RDMs, add them to the newly reimaged VM.