Adding Hosts with Different Processors to a vSAN Cluster

Products

• VMware vSAN

Issue/Introduction

When adding new hosts to a vSAN 8.x cluster, if the new hosts have the same memory and storage but different processors compared to existing hosts,
there may be concerns about the impact of processor differences on the functionality and performance of the vSAN cluster.

Environment

 vSAN 8.x

Resolution

1. Support for Asymmetrical vSAN Clusters:

Adding hosts with different processors to a vSAN 8.x cluster is supported. This configuration is known as an asymmetrical vSAN cluster, where one or more hosts have different hardware (e.g., processors or storage devices) compared to others in the cluster.

• Asymmetrical Clusters: In an asymmetrical cluster, hosts may contribute varying hardware characteristics, such as differing processors or storage devices. While this configuration is supported, following best practices is important to ensure optimal performance and compatibility.
• For further guidance on configuring asymmetrical vSAN clusters and understanding the potential impacts, refer to the VMware blog:
  Asymmetrical vSAN Clusters – What is Allowed, and What is Smart?

2. Enabling EVC for Processor Compatibility:

To ensure proper migration of virtual machines (VMs) between hosts with different processor generations, it is recommended to enable Enhanced vMotion Compatibility (EVC) on the cluster.

• EVC ensures that VMs can be migrated across hosts with different processors from the same vendor, while avoiding potential compatibility issues.
• Enabling EVC ensures that all hosts in the cluster present a consistent CPU feature set to virtual machines, enabling proper VM operation and migration.

For more detailed information about configuring EVC and managing CPU compatibility in vSAN 8.x, refer to the following VMware article:
VMware EVC and CPU Compatibility FAQ

Summary:

• Hosts with different processors can be added to a vSAN 8.x cluster, but this configuration should be carefully managed to ensure optimal performance.
• Enabling EVC ensures smooth migration of virtual machines between hosts with different processors.
• Refer to the provided resources for additional guidance on configuring asymmetrical vSAN clusters and ensuring CPU compatibility across hosts.

For further assistance with configuration or any related questions, please refer to the available documentation or reach out to VMware support.

Additional Information

• 異なるプロセッサを搭載したホストを vSAN クラスタに追加する