I'm new to VSAN and I'm trying to do a quick calculation on storage.
Minus the SSD's I have 4 hosts each with 8TB of storage. With a FTT=1, does that give me roughly 16TB of usable storage for VMs?
Yes, you are correct. FTT 1 is mirroring, each component will have a mirror copy, that case usable space will be approximately total size / 2 which is 16TB in your case.
You are right about your calculation but there are other parameters as well which we should consider while sizing vSAN. If you are looking for correct sizing, please refer to vSAN TCO - https://vsantco.vmware.com
vSAN is quite different from traditional storage arrays in terms of Sizing.
Hope this answers your query!
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