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"so which version of V-SAN my servers support and i can run?"
What determines what versions (if any) of vSAN are supported to run on a server are:
1. Server is supported for ESXi version you intend to run - the 2 variant I can find on the vSAN HCL are supported up to ESXi 6.7 U3, but the physical servers were end-of-sale in 2016 so doubtful 7.0 support will manifest:
2. Controllers in use for vSAN are on the vSAN HCL for the verion of vSAN in use - I see no ReadyNode listings for this model but Cisco boxes configured for vSAN *usually* have standard 12G Modular SAS controller which is supported for everything including vSAN 7.0:
3. Cache-Tier drives (SSD/NVMe) are on the vSAN HCL for the verion of vSAN in use and for the intended purpose (e.g. don't use a Read-intensive SSD certified only for All-Flash Capacity-tier as Cache-tier and expect not to have a bad day).
4. Capacity-Tier drives (HDD/SSD/NVMe) are on the vSAN HCL for the verion of vSAN in use.
Handy tool for checking if devices are on the HCL:
"and how can you leading me ?"
The plan for designing/re-purposing a cluster is your responsibility - though do feel free to ask questions, that's what this Community is for.
"how many blade i need for starting V-SAN?"
A minimum of 3-nodes (servers here) is required for a basic FTT=1,FTM=RAID1 configuration, a minimum of 4-nodes (and All-Flash storage and Advanced licensing) is required for a FTT=1,FTM=RAID5 configuration,
"and how much capacity can i use for cache and capacity disk?"
There are no maximums to the size of the disks that can be used other than that you won't find anything absurdly large on the vSAN HCL - most of our customers use 400GB-1.2TB Cache-tier devices and 1-4TB Capacity-tier devices. Each Disk-Group is composed of exactly 1 Cache-Tier device (SSD/NVMe) and 1-7 Capacity-Tier drives (HDD/SSD/NVMe), 5 Disk-Groups per node is the maximum.
IMO the current sweet-spot with regard to price-point and performance (for All-Flash) is likely ~800GB for Cache-Tier (unless going P4800x NVMe in which case 400GB will likely do) and 2-4TB Capacity-Tier with 3-5 per DG.
by the way thanks for your help
1- Can lower versions be installed according to your description? like ESXI 6.5 U3?
2- My controller model on servers is "1GB flash backed write cache for LSI 2208R " , which is not given in the link, that is, does it not support the Vision V-SAN?
3- Can i use other brand Disk ( like sumsung or... )