VMware Cloud on AWS Outposts

Introducing multi-rack and multi-cluster capability for VMware Cloud on AWS Outposts

VMware introduced VMware Cloud on AWS Outposts in Oct of 2021, offering LCaaS (Local Cloud as a Service) to customers’ data center locations.  

VMware Cloud on AWS Outposts represents the latest joint engineering effort between VMware and AWS. The solution is powered by VMware’s enterprise-class Software-Defined Data Center (SDDC) software for compute (vSphere), storage (vSAN), and networking (NSX) along with vCenter Management, which runs on next-generation, dedicated Amazon Nitro-based EC2 bare-metal instances provisioned in AWS Outposts.

Since the general availability of VMware Cloud on AWS Outposts, we have been introducing new features and capabilities for this service. Today, we are excited to announce a new capability- multi-rack, multi-cluster support for VMware Cloud on AWS Outposts. In this blog post, let’s look at some of the details of the offering and capability.

What’s multi-rack and multi-cluster?

VMware Cloud on AWS Outposts is tailored for workloads that are required to remain on-premises.  As businesses grow, customers need a highly scalable IT infrastructure in their data center that keeps pace with additional workload demands.

To address customers’ scalability challenges of their Local Cloud infrastructure, we are introducing multi-rack and multi-cluster support for VMware Cloud on AWS Outposts. It offers customers a scalable infrastructure that supports multi-rack configuration to handle scalable deployment of multiple workloads. With this new capability, customers can now order multiple AWS Outposts racks and scale out the infrastructure by adding hosts within multiple racks. Customers can also create multiple clusters on the rack and group hosts with multiple clusters for flexible workload management.

A workload domain is a logical abstraction of compute, storage, and network cloud capacity and consists of one or more clusters. The multi-cluster feature supports creating and managing multiple clusters in a single SDDC across multiple racks. However, each cluster can span across multiple racks for redundancy. Workload domains can be tailored for different sizes, you map workload domains to VMware Cloud on AWS Outposts racks according to your requirements and physical infrastructure constraints.

What’s new with multi-rack and multi-cluster capability?

  • More capacity: Up to 16x compute and storage capacity as compared to single rack configuration. Dedicated capacity for customer workload without management VM overhead.
  • Increased Scalability: Ability to easily scale out existing deployments or design new deployments as per the business needs as well as scalability for network traffic with multi-edge and large SDDC support
  • A maximum of up to 16 racks is supported in a multi-rack configuration.
    • Multi-Edge feature support.
    • Custom core support.
    • Run time scale-up and large SDDC support.
  • Simplified Network connectivity: The ACE (Access,Core,Edge) rack consolidates physical network connection of the multi-rack deployment and provides a single point of interconnectivity with the customer network devices (CND’s), greatly reducing network port requirements. The lack of an ACE Rack could exhaust the ports on the CNDs for large multi-rack deployments. The ACE rack would be provided when ordered beyond 4 racks.
  • Increased flexibility: Ability to separate workloads based on performance/capacity/security requirements between multiple clusters to support architecture and workload design requirements.
  • Improved resiliency: More resilient infrastructure across multi-rack with spare capacity as a part of auto-remediation and fault tolerance.

Multi-rack and Multi-cluster feature technical overview:

Now let’s look at some technical details of this capability.

Overview of a multi-rack and multi-cluster configuration

VMware Cloud on AWS Outposts in multi-rack configuration utilizes multiple physical racks, with each rack containing AWS Outposts bare metal hardware used as compute resources, and networking devices to provide connectivity within the rack, between racks and redundant top-of-rack switches called Outposts Networking Devices (ONDs).

  • Each OND is connected to a separate customer-managed switch called a Customer Networking Device (CND). This provides diverse physical and logical paths for each AWS Outposts rack. ONDs connect to your CNDs with one or more physical connections using fibre optic cables and optical transceivers.
  • The  OND to CND physical connections are configured in logical link aggregation group (LAG) links even if the physical connection is a single fibre optic cable. Configuring the links as LAG groups allows you to increase the link bandwidth by adding additional physical connections to the logical group. The LAG links are configured as IEEE 802.1q Ethernet trunks to enable segregated networking between the Outposts and the on-premises network.
  • Between the AWS Outposts racks, the ONDs are redundantly interconnected to provide highly available network connectivity for workloads running on the servers. AWS is responsible for network availability within the AWS Outposts.
  • In multi-rack deployments with an ACE Rack, Customers can choose physical network speeds between 10G, 40G, and 100G for connection between CND and ACE Racks. However, the connection between ACE Rack and OND can only be 100G.
  • EC2 bare metal instances are automatically spread across all the racks through a Partition Placement Group (PPG). The currently supported hardware instance type is i3en.metal. Hardware specification can be found here.
  • In a single rack, workload domain can occupy exactly one rack. In a multi-rack and multi-cluster configuration, workload domains can be spread across multiple racks mapped to different clusters based on your workload needs.
  • Single pane of glass view for managing multiple racks from a single console for operational simplicity.
  • Auto-remediation support with spare capacity for high availability.

Technical deep dive for VMware Cloud on AWS Outposts can be found here.

How the order flow works for VMware Cloud AWS Outposts:

If you would like learn more about the order flow, please check out  the demo walk-through video: “How to order a VMware Cloud on AWS Outposts”  


Designed for customers who wish to leverage the cloud operating model on-premises for business use cases such as latency, data gravity, data sovereignty/compliance or data center modernization needs. VMware Cloud on AWS Outposts is tailored to meet such business needs where customers can focus on strategic business priorities rather than focusing their resources on managing infrastructure. And this newly launched multi-rack and multi-cluster capability will provide you with more flexibility and scalability in terms of workload management.

To learn more about VMware Cloud on AWS Outposts, check out the resources below: