Memory Controller Scrubbing Error and Memory Controller Read Error are detected on the vCenter Server

Products

• VMware vSphere ESXi
• VMware vCenter Server

Issue/Introduction

In the vSphere Client, an event such as "MCA:196:UCNA Poll GO Be Sfc007700040004000c1 A############# M############### P##########/## Memory Controller Scrubbing Error (YYYY-MM-DDThh:mm:ss.###Z cpu#:########)" will be displayed on the ESXi host's "Events" screen, and a "Host Error" alarm will be triggered for that ESXi host.

In addition, an event such as "MCA:196:UCNA Poll GO Be Sfc007700040004000c1 A############# M############### P##########/## Memory Controller Scrubbing Error (YYYY-MM-DDThh:mm:ss.###Z cpu#:########)" will also be detected on SNMP servers monitoring the ESXi host.
Similar messages are also recorded in the vmkernel.log of the affected ESXi host.

Environment

VMware vSphere 7.x
VMware vSphere 8.x

Cause

This issue is a hardware-related issue caused by a scrubbing error or read error in the host's memory controller. It occurs when an error is detected during the scrubbing process, in which the memory controller periodically references and checks memory cells, or when these memory controller errors are reported by the CPU. These errors are caused by hardware issues.

Resolution

If you experience this issue, please contact your hardware vendor and have them investigate the issue from a hardware perspective.

For more information on MCA, please also see KB below.
Decoding Machine Check Error (MCE) output after an ESXi panic (Purple Screen)