3 Replies Latest reply on Mar 12, 2019 7:03 AM by dongjh

    vSAN Design and Sizing Guide 6.5 miscalculation?

    Krenztor Enthusiast

      I'm going through the VMware vSAN Design and Sizing Guide 6.5 trying to get a better grasp on vSAN.  Going through "14.2 Capacity Sizing Example II" I want to verify that the calculations done for "option 3 All Flash" are correct.  After calculating the Snapshot Storage Consumption the following calculation for Raw Storage Requirements (VMs + Snapshots) is listed as 49.87 TB + 2.5 TB.  The 49.87 TB is pulled from the cache size calculation which in previous examples was only used to get the Snapshot size.  I think that in place of 49.87 TB it is supposed to use 66.5 TB from the Raw Storage Requirements calculation.

       

      I am very new to vSAN so I can't say for sure that this is a miscalculation but I can't find any instructions in the document that would explain why All Flash is calculated differently on these lines compared to Hybrid.  I'd appreciate it if someone with more experience with vSAN could let me know what is correct.  Thanks!

       

      Also worth noting is that the lines "Raw Formatting Storage Capacity = 261.6/0.7" and "Raw Unformatted Storage Capacity = 373/0.99" are copy and pasted from a previous example and not applicable to the calculation for All Flash.

       

      https://storagehub.vmware.com/export_to_pdf/vmware-r-virtual-san-tm-design-and-sizing-guide