Description

vMX installed on ESXi servers does not work in performance mode inspite of using the latest processors (Intel Ivy Bridge processors or later) and meeting all requirements according to the Minimum Hardware and Software Requirements

Symptoms

In the VFP console log collected during reboot, it shows the processor does not support the RDRAND feature, which is required for vMX to work in performance mode.

ERROR: This system does not support "RDRAND" 
Please check that RTE_MACHINE is set correctly.
EAL: FATAL: unsupported cpu type. 
EAL: unsupported cpu type.
VMXT not running. sleeping

Solution

This is caused by wrong Enhanced vMotion Compatibility (EVC) mode configuration on the server. EVC is a feature in VMware vSphere virtualization that allows virtual machines (VMs) to move between ESXi hosts on different CPUs. After EVC is enabled for a cluster, all hosts in that cluster are configured to present identical CPU features and ensure CPU compatibility for vMotion.

If the VMX installed on ESXi servers does not work in performance mode in spite of using the latest processors (Intel Ivy Bridge processors or later) and meeting all the minimum requirements, it is possible that EVC mode is set to Sandy Bridge or older processors which does not support the RDRAND feature that came with Ivy Bridge generation. Changing the EVC mode to support at least Ivy Bridge capabilities should bring up the VMX in performance mode.

For information about EVC and how to change the EVC mode in a cluster, refer to the following VMware KB articles:


 

Related Information