VMware vSAN Solution Analysis

VMware vSAN is a distributed software solution that runs natively as a part of the ESXi hypervisor. It follows HCI architecture with vSphere and NSX solution. And importantly this solution was first introduced in the year 2014 and has more than 30000+ customers worldwide

Target Buyers and Typical Use Cases

Customers who run a vSphere environment and looking for shared storage with data at rest encryption, and have the plan to make use of private/hybrid cloud can be a good candidates for this solution. From the scale perspective, customers with 50+ VMs, are advised to evaluate this solution, and further, it can be extended to environments such as ROBO sites, VDI, Disaster recovery, etc.

Deployment Model and Considerations

Hardware Selection: VMware only provides software for this solution. And for the hardware part, VMware relies on external ecosystem vendors. There are primarily two options for the hardware 1) vSAN ready nodes from approved OEM or 2) Use engineered/ruggedized platform systems such as Dell EMC VxRAIL

All Flash or Hybrid: Depending on the customer scenario the solution can be deployed for the single site or stretched between multiple sites ( stretched cluster) and for the storage it can go with a flash/NVMe-only model or hybrid ( Flash/NVMe disk for the caching/buffering tier and magnetic disk for the capacity/data tier)

Clustering Considerations: The minimum of three nodes vSAN cluster model is used for ensuring the required high availability, however, four hosts will allow for maintaining levels of prescribed resilience in the event of failure.

Disk Group Considerations: Specify the hosts with at least two disk groups. Two or more disk groups on a host allow the host to still continue to provide storage capacity in the event of a disk group failure

Physical Connectivity: Consider having a minimum of 10G physical connectivity ( for all-flash configuration) capacity between the host nodes in the vSAN cluster. And 25G/40G or 100G bandwidths are supported as well

Competition

The major competition for this solution comes from existing vendors such as Nutanix, Scale Computing, Pivot3, StorMagic, Starwind, etc

Sizing Guidelines

Tools and compatibility: Proper sizing and design exercises are very important for making the VSAN solution future-proof. Before deploying the solution it is recommended to use existing infrastructure assessment tools such as LiveOptics, and DICE and also use VSAN ReadyNode Sizer and VMware compatibility guide.

Capacity Sizing: Once the existing environment information is available, the application performance and capacity requirement also need to consider to select the correct replication factor ( RF1, RF2, or RF 3). And based on that net usable capacity calculation could be derived. For example, if the number of failures to tolerance is set to 1 in the virtual machine storage policy, then there is another replica of the VMDK created on the capacity layer on another host (two copies of data). If it is set to two then there are two replica copies of the VMDK across the cluster ( three copies of the data)

Scale/Configuration Limits: Some of the interesting limits include such as with vSAN all-flash configuration allows a maximum of 64 nodes/hosts in a cluster and allows up to 62 TB for VMDK size

Licensing and Pricing

The licensing and pricing are based on the specific use cases of the customer, below are the common licensing tiers and sample list pricing details.

Summary

The vSAN requires a good number of considerations such as network, storage, computing, clustering, and importantly determining workload suitable for vSAN. This blog post primarily focused on giving you the key areas to focus and for detailed information please refer VMware sizing guidelines document.