“If you can’t explain it simply, you don’t understand it well enough.”
Albert Einstein
I have an impression that for Pre-sales Engineers it is harder than for others ;-). Especially when you need to explain the benefits of a complex solution in a simple but also short way.
Keep it Sesame Street Simple, they say.
I am practicing my SSS skills on vSAN…
Usually in traditional 3 -Tier architecture under every vCenter we have a long list of datastores backed by different LUNs created on storage arrays from different vendors having various settings: mirrored LUN, RAID-10/5/6, deduplication ON/OFF, synchronous and asynchronous replications. They are thin-provisioned and have various used/free ratios. Admin can identify a suitable datastore for a VM by a name or a tag but it is not always sufficient, especially when storage and compute resources are managed by different teams. VMs can have many VMDKs with different performance and resilency requirements. How to keep it all in order?
With vSAN there is always one datastore per cluster. It uses storage policies that can be assigned on per-VMDK basis. This allows to allocate storage resources granularly and with an application requirements in mind.
vSAN makes storage management way more easier. It also simplifies the troubleshooting process. You do not have to figure out which datastore is used by the particular VM and troubleshoot it individually. The storage path from a VMDK to a physical disk can be tracked and analyzed in details in a vCenter.