Understanding vSAN Data Persistence Platform

Modern applications depend on modern stateful services, such as object storage, NoSQL databases, and event streaming services for their persistence needs. Over the past few years, we’ve seen an increasing amount of interest from customers desiring to run modern stateful services on vSAN. As a result, VMware announced support for scalable, S3 API compatible, multi-tenant storage on VMware Cloud Foundation™ with VMware Tanzu™ will support scalable, S3 API compatible, multi-tenant storage. It’s called the vSAN Data Persistence platform (DPp).

vSAN Data Persistence Platform

Most modern stateful services are designed in a shared-nothing architecture and have data services such as replication and encryption natively built-in. Deploying such modern distributed systems requires rethinking storage assumptions about what features and capabilities should be provided by the infrastructure.

vSAN DPp provides a framework for modern stateful service partners to interoperate with the underlying VMware infrastructure so that their software can run on VMware Cloud Foundation™ with VMware Tanzu™ optimally. The result is that you can run modern stateful services with lower TCO and simplified operations and management.

Simplified Service Deployment and Operations

Enabling a third-party k8s operator and plugin for DPp is as easy as a few clicks in vCenter. The vSAN DPp takes care of the rest: spawning the relevant third-party operator, and creating the necessary container storage classes and vSAN storage policies. The optional partner UI plugin exposes the monitoring and management details of the application.

Provisioning Stateful S3 Object Stores

Once the service is enabled, there are three simple steps for admins to provide object interfaces and stateful services for developers.

Create a Namespace – The Namespace is a virtual cluster that stores all the relevant pods to support an object storage instance. This is where you assign permissions and determine which storage policies are to be used.
Create an Instance – Instances are created (inside namespaces) in vCenter by administrators or via the Kubernetes API by the dev team. This is where you can select the backend storage, erasure coding, encryption, and other advanced features.
Create a bucket – Once the instance\tenant is online, authenticated users can provision and manage S3 object buckets.

Deployment Options

The vSAN Data Persistence platform supports two deployment options for modern stateful services including object storage.

Option 1: vSAN Shared Nothing Architecture (SNA)

Option 2: vSAN Direct Configuration

vSAN Shared Nothing Architecture

vSAN-SNA consolidates traditional and modern apps in the same vSAN Cluster with optimal storage efficiency. This option provides a fast and convenient way to get started with running modern stateful services on vSAN. By choosing the vSAN-SNA storage policy, customers can leverage the availability features that come with the modern stateful services and have replication turned off in the vSAN layer for minimum storage overhead and space savings. This option is ideal for customers who want to run modern stateful services alongside traditional apps on the same vSAN Cluster or use general-purpose infrastructure for modern stateful services with various workload characteristics.

vSAN Direct Configuration

vSAN Direct configuration allows modern stateful services to use the availability, efficiency and security features built into the modern stateful service layer, and have direct access to the underlying direct-attached hardware for optimal storage efficiency and near bare-metal performance. Unlike vSAN-SNA where storage objects for traditional and modern apps reside in the same vSAN Datastore, storage devices are provisioned as individual datastores in vCenter. vSAN DPp manages the placement of the data to ensure that applications providing their own resilience, have data placed in different fault domains. Visibility of the devices and datastores contributing to a vSAN Direct Configuration can be easily viewed through the Datastores view in the vCenter Server UI.

vSAN-Direct is ideal for purpose-built deployments of a certain modern stateful service where the underlying hardware can be optimized for workload requirements. Primary use cases include:

Dense S3-compatible object storage for archival or data with infrequent access
Performance sensitive apps such as those for Big Data and advanced analytics.

Health and Capacity Monitoring

The primary concern of the vSphere administrator is ensuring workloads and the infrastructure is healthy. vCenter has always been at the center of operations for anything in the vSphere datacenter, this was extended to vSAN when it was introduced, and it has again been extended to include the vSAN Data Persistence Platform.

With vSAN DPp, partners gain the ability to build out vCenter native UI plugins to bring application-specific operations right into vCenter. This varies from vendor to vendor, as all apps are different, but as an example, you could increase storage allocation for a particular S3 Object Store, choose to repair application data should a node go down, monitor the health status of not only the application but of individual volumes and nodes within the application itself. vSAN DPp also offers partners the ability to integrate their plugin with the vSphere Skyline Health framework, plugging application-level health awareness right into the vSphere environment.

vSAN administrators are already accustomed to robust and granular capacity and performance monitoring. This now includes monitoring of S3 Object Store instances from vSAN DPp. Administrators can view current and historical capacity information for both vSAN-SNA and vSAN-Direct Object Storage. In addition, capacity can be monitored at the instance, cluster, node, and individual disk level.

Service-aware infrastructure Operations

Administrators should have visibility into modern stateful services and insights into how infrastructure operations, such as planned maintenance and lifecycle management, will impact the availability of modern stateful services. For planned infrastructure operations such as maintenance and lifecycle management, the vSAN Data Persistence platform ensures that the modern stateful services are made aware of the upcoming infrastructure operations and can coordinate activities with the infrastructure changes to keep the services up and running.

Failure Handling

Modern stateful services have built-in resilience and are designed to maintain availability in the event of object failure. Independent Software Vendors (ISV)s like MinIo and Cloudian protect data with per-object inline erasure coding written in assembly code to deliver the highest possible performance. Objects are striped into data and parity blocks with user-configurable redundancy levels. The built-in erasure coding performs healing at the object level and can heal multiple objects independently. While Erasure Coding healing is automatic and enabled by default, long-term resolution of the following failures requires user intervention:

Server failure, such as a downed ESXi host or a locked pod.
Volume failure, such as a physical drive failure or bad Persistent Volume configuration.

Some ISV plugins offer the ability to kick off repair operations directly inside the vCenter UI, should an application be in a degraded, but available, state due to failed hardware. For details on failure handling capabilities, be sure to check with your Independent Software Vendor.

Summary

The vSAN Data Persistence platform provides a framework for modern stateful service partners to interoperate with the underlying VMware infrastructure so that their software can run on VMware Cloud Foundation™ with VMware Tanzu™ optimally. The result is that you can run modern stateful services with lower TCO and simplified operations and management.

We believe the vSAN Data Persistence platform is the first step in a very exciting journey to make VMware not only the best platform for VMs, but for all workloads. More than that – vSphere is clearly now evolving from an infrastructure platform into a services platform. A platform where you don’t deploy onto – you simply enable and consume.

Resources

Check out the blog announcements by our partners for more details about each partnership:

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