Principal and Supplemental Storage in VMware Cloud Foundation 5.1
Key Points
- VCF supports a wide variety of storage types including vSAN, vVols, VMFS, and NFS
- VCF 5.1 introduced support for vSAN ESA, providing improved performance and efficiency
- vSAN is the recommended storage for VCF because it provides a full private cloud experience with automated workflows and lifecycle management
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VMware Cloud Foundation (VCF) is Broadcom's private cloud solution that is built on compute, networking, and storage virtualization, providing customers with the ability to implement a cloud operating model on-premises. It offers benefits such as ease of deployment, lifecycle management using a pre-validated Build of Materials (BOM) which is rigorously tested for interoperability, and automated provisioning of infrastructure resources.
Storage, a critical part of the private cloud, is supported in two categories: Principal and Supplemental.
PRINCIPAL STORAGE
Principal storage is configured when creating a new Workload Domain or a cluster in SDDC Manager. Once created, the principal storage type for a cluster cannot be changed. However, a VI Workload Domain can include multiple clusters with unique principal storage types.
Principal storage options include vSAN, vVols, NFSv3, and VMFS on FC. Note that vSAN is the only supported Principal Storage type for all clusters in the Management domain. vSAN is required for the management domain because it’s predictable. vSAN provides a highly performant enterprise class storage solution for the SDDC. The use of vSAN eliminates outside dependencies and facilitates the use of automation to instantiate the VCF Management Domain. During the initial deployment of VCF, Cloud Builder bootstraps all of the core software-defined data center components like vSphere, NSX, and vSAN onto the minimum required hosts. This 'bring up' process, on average, takes approximately 2 hours to complete.
SUPPLEMENTAL STORAGE
Supplemental storage provides additional capacity to the cluster and is recommended for tier 2 or tier 3 data, such as vSphere Content Libraries, virtual machine templates, backup data, ISO images, etc. Supplemental storage requires manual configuration and is not integrated or shown within SDDC Manager.
Available options include vSAN, vVols, VMFS on FC or iSCSI, NFSv3 or v4.1, and NVMe-FC or NVMe-TCP.
Supported Storage Types for VMware Cloud Foundation
vSAN ESA
As of 5.1, vSAN supports both OSA (Original Storage Architecture) and ESA (Express Storage Architecture). vSAN ESA is optimized for next generation high performance NVMe storage devices to provide even higher levels of performance for demanding workloads such as OLTP and Generative AI. Broadcom recommends using vSAN ESA as the principal storage for all Workload Domains to leverage the benefits of managing and maintaining a full software defined stack.
vSAN is also updated and patched through SDDC Manager LCM. Updating and patching non-vSAN storage is a manual task and falls outside of the lifecycle management offered by SDDC Manager. To ensure supportability, the storage and HBAs will need to be validated against the VMware Compatibility Guide, when vSAN is not being used.
vSAN leverages Storage Policy-Based Management (SPBM) which allows you to manage your storage capabilities via storage policies, at the VM level rather than the entire Datastore. With vSAN’s policy-driven control plane, you can easily manage storage in VCF. When thinking in terms of scale, being able to use a programmatic approach to storage management is key. Manually managing LUNs or volumes and storage capabilities at scale isn't easy.
For more information on the benefits of SPBM as well as Why vSAN and vVols are Best for VMware Cloud Foundation, please refer to the embedded article.
SUMMARY
vSAN is the recommended principal storage solution for workloads for the reasons mentioned above. However, we understand that not all customer environments are the same, and a 'one-size-fits-all' approach does not work. This is why VCF supports a variety of primary and supplemental storage types. This flexibility with other storage options provides customers with the power of choice and allows VCF to meet the diverse needs of customer environments.
It's important to understand the broad set of requirements such as performance, availability, capacity, expected growth, and existing investments. To that end, for additional VMware Cloud Foundation information and storage requirements, please refer to the following resources.