vsan 7.x all flash 3 node design

[orddie]

 Hi All.

Putting my vMug to good use and doing a vsan deployment in lab.

I plan to use intel optane as cache disks and intel 1.9 TB SSD's as capacity.

I will use three nodes with a FTT of 1 and disk stripes of 2.

Deduplication and compression will be enabled.

Network will be 10 GBE.

The question to the group is how many cache to capacity?  Some blogs mention 10%, 30%, 1:3 or 1:1.

[TheBobkin · Accepted solution]

@orddie, Cache:Capacity ratios are referring to size of the Cache-tier device to the total Capacity-tier of the Disk-Group, not the number of Capacity-tier devices in the Disk-Group.

E.g. 400GB Cache-tier + 2x 2TB Capacity-tier in a Disk-Group would be 10% ratio.

Not to over-complicate things but do note that these ratios are usually based on used capacity not available capacity.

If you are going with stripe-width=2, single Disk-Group per node in a 3-node cluster then that would require a minimum of 2 Capacity-tier devices in each Disk-Group.