This brief and high level implementation example will provide a sample use case for the utilization of VMware Virtual SAN in a vCloud Director for Service Providers environment.
Outlined in the illustration below, each Provider Virtual Data Center / Resource Cluster has been configured with a Virtual SAN datastore that meets the specific capability requirements set out by their Service Level Agreement (SLA) for that tier of service.
In this example, the service provider is deploying three tiers of offerings, Gold, Silver and Bronze. The compute consolidation ratio and virtual SAN capability, based on the disk group configuration and storage policy, defines how the offering will perform for a consumer. In addition, not shown in the configuration below, NIOC and QoS are being employed by the service provider to ensure an appropriate balance of network resources are assigned, based on tier of service. This requires the configuration of 3 separate tiered VLANs for Virtual SAN traffic (Gold, Silver and Bronze) with traffic priorities configured accordingly.
The exact disk configuration will vary depending on hardware manufacturer and provider SLAs.
Logical Design Overview
The full VMware technology solution stack is illustrated below.
The above figure shows how the solution is constructed on VMWare technologies. The core vSphere platform provides the storage capability through Virtual SAN, which in turn is abstracted via vCloud Director. The VSAN Disk Group configuration across the hosts, along with the Storage Policy, that is configured at the vSphere level, define the performance and capacity capabilities of the distributed datastore, which in turn is employed to define the SLAs for this tier of the cloud offering.
As is illustrated above, the vSphere resources are abstracted by vCloud Director into a Provider Virtual Data Center (PvDC). These resources are then further carved up into individual Virtual Data Centers (vDC), assigned to Organisational tenants. The overall result is that the vApps that reside within the Organizational vDCs represent the Virtual SAN storage capability defined by the service provider.
Typically, but outside the scope of this discussion, tiered service offerings are defined by more than just storage capability. vCPU consolidation ratios, levels of guaranteed memory and network resources and backups etc. will all be employed by a service provider to define the SLAs.
As I develop this use case for the service providers I’m working with I will update this article further.