Failed to read the device <Device:Partition> : Not found

Products

• VMware vSphere ESXi

Issue/Introduction

When performing ESXi host patching, or upgrades the host disconnects from vCenter and fails to patch. Reviewing the vmkernel and vmkwarning logs shows entries stating failure to read device <device:partition> : Not Found. And the device in question holds the OSData boot partition. 

Environment

ESXi 

Cause

This is as the log states a failure to read data from the boot device. 

Resolution

Engage hardware vendor to perform a diagnostic health check and replace faulty components, reinstalling ESXi if necessary.