Module CPUID power on failed. Failed to start the virtual machine. The current EVC mode is masking features SSE 4.1 SSE 4.2 POPCNT required by rhel9-64 guests. This virtual machine cannot be powered on.
Article ID: 402445
Updated On:
Products
Issue/Introduction
A virtual machine cannot be powered on within an affected cluster. The power-on task fails, and the following error is generated within the vCenter Server tasks or ESXi host logs:
Module CPUID power on failed. Current EVC is masking feature SSE 4.1 SSE 4.2 POPCONT required by the VM. This virtual machine cannot be powered on.
Environment
VMware vSphere 8.x
VMware vSphere 7.x
EVC enabled vSphere Cluster.
Cause
This issue occurs when the virtual machine resides in an Enhanced vMotion Compatibility (EVC) enabled cluster configured with a legacy EVC baseline, such as "Intel Merom".
Legacy baselines are architecturally designed to deliberately mask modern CPU instructions, including SSE4.1, SSE4.2, and POPCNT, to ensure vMotion compatibility across older hardware generations. The virtual machine is prevented from powering on because the guest operating system explicitly requires these masked instructions to execute its boot sequence.
Resolution
To resolve this issue, the CPU features required by the virtual machine must be made available at the cluster level. One of the following options must be implemented:
Option 1: Increase the Cluster EVC Mode
The physical CPUs of all ESXi hosts within the cluster must be verified to natively support a higher EVC mode.
The EVC settings must be accessed via the vSphere Client by navigating to: Clusters > Configure > vSphere EVC > Edit.
The EVC mode on the cluster must be increased to a baseline that supports the required instructions (e.g., "Intel Nehalem", "Intel Haswell", or a newer generation).
The virtual machine power-on task can be retried once the cluster EVC reconfiguration is successfully completed.
Option 2: Disable EVC on the Cluster If all ESXi hosts within the cluster are equipped with identical physical CPUs, EVC functionality may not be required. EVC can be disabled on the cluster to expose all native hardware CPU instructions to the residing virtual machines.
Option 3: Relocate the Virtual Machine The virtual machine can be migrated to a different cluster where the EVC baseline is already configured to "Intel Nehalem" (or a newer generation) that supports the required CPU instructions.
Important Consideration Regarding Per-VM EVC: Per-VM EVC cannot be utilized to circumvent this limitation. If a virtual machine is located within an EVC-enabled cluster, the Per-VM EVC mode is architecturally restricted from exceeding the EVC mode established for the parent cluster.
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