Hello CERKYR,
Just a reminder that this is an English-speaking Sub-community and thus you will increase the chance you get answers by a) using Google translate or posing questions in English or b) posting on language-specific sub-communities e.g. French
Via Google-translate:
In order to activate a VSAN (witness), I need to make a quote for SSDs needed.
The goal is to buy at least 4 (2 per server) (including 1 in SPARE online per server).
I remind you that a big part of the SAS disk of each of the 2 ESX will be used for the VSAN.
Has VMware validated a list of SSDs for DELL R740?
What capacity (GB) is required for these SSDs?
The goal is to be able to make an estimate.
I hope that the VSAN will allow the execution of a VM regardless of where this VM will be stored in the VSAN, especially in case of failure of one of the 2 ESX, with automatic restart of the VM with the other ESX, thanks to the HA features.
Firstly, just to explain a bit about how vSAN works:
We use (typically) smaller and faster SSDs for cache-tier and then (typically) larger lower performance SSDs for capacity-tier - note that the cache-tier does not contribute any space to the size of the vsanDatastore only the capacity-tier devices.
While having hot-spares on hand is always a good idea, providing enough slack-space that everything can be rebuilt can avoid this being necessary and then replace failed devices when/if this occurs.
Witnesses do not require a physical server to run on and this is a tad wasteful/expensive in my opinion - it sounds like you are planning a 2+1 (DirectConnect) or 1+1+1 (stretched) cluster, if you have some other environment (e.g. ESXi with SAN/NAS) you can run the Witness as a Appliance VM or alternatively host this on the cloud etc.
"Has VMware validated a list of SSDs for DELL R740?"
We do not validate/certify devices just for any specific server - any of our certified devices can be used in ESXi-compatible servers, you can check what is certified here:
(click "Build Your Own based on Certified Components.")
https://www.vmware.com/resources/compatibility/search.php?deviceCategory=vsan
and here:
https://hcl.captain-vsan.com/
"What capacity (GB) is required for these SSDs?"
It is unclear from what you said whether you are just looking for sizing devices for a Witness or as cache-tier or capacity-tier as the vSAN storage - please clarify this.
Default Witness sizings are like so:
Tiny (10 VMs or fewer)
2 vCPUs, 8GB vRAM
8GB ESXi Boot Disk, one 10GB SSD, one 15GB HDD
Supports a maximum of 750 witness components
Medium (up to 500 VMs)
2 vCPUs, 16GB vRAM
8GB ESXi Boot Disk, one 10GB SSD, one 350GB HDD
Supports a maximum of 21,000 witness components
Large (more than 500 VMs)
2 vCPUs, 32GB vRAM
8GB ESXi Boot Disk, one 10GB SSD, three 350GB HDDs
Supports a maximum of 45,000 witness components
Bob
