ESXi fails to boot on an Intel CPU powered HPE Superdome Flex host

Products

• VMware vSphere ESXi

Issue/Introduction

This article provides a workaround to the Intel CPU powered HPE Superdome Flex server issue.

Symptoms:

• HPE Superdome Flex servers with some Cascade Lake processors (Intel Xeon Platinum 8200 Series, Intel Xeon Gold 6200 Series) or with some Skylake processors (Intel Xeon Platinum 8100 Series, Intel Xeon Gold 6100 series) may stop responding or fail to boot when ESXi loads certain specific versions of Intel CPU microcode.
• You are running one of these versions:
  • ESXi 6.7p05 (ESXi670-202103001)
  • ESXi 7.0 Update 2
  • ESXi 7.0 Update 2a
• Running this command returns one of the affected microcode versions:

vsish -e get /hardware/cpu/cpuList/0 | grep 'Current Revision'

• Cascade Lake microcode versions 0x04003003 and 0x05003003
• Skylake microcode version is 0x02006a08.  

 

Environment

VMware vSphere ESXi 7.0.x
VMware ESXi 6.7.x

Cause

This issue is caused by a regression in the Intel CPU microcode.

Resolution

Currently, there is no resolution.

Workaround:
Note: Do not apply this workaround if your system is not affected by the specific issue in this KB article.

To work around this issue, disable the  ESXi's CPU microcode loader by setting the vmkernel boot option VMkernel.boot.microcodeUpdate to false, then reboot. for more information on how to change advanced settings, see Configuring advanced options for ESXi/ESX

To set this option using SSH and command line:

1. Connect to the ESXi host with an SSH session and root credentials
2. Run this command:

esxcli system settings kernel set --setting=microcodeUpdate --value=false