topic vSAN with 3 node in VMware vSAN Discussions

vSAN with 3 node

abckdc — Sun, 01 Aug 2021 07:58:03 GMT

Hello EveyOne,

I am running vSphere 7 in my test environment and I am working with 3 host (new to the environment). I am looking towards deploying vSAN in my enviromnment where two host have local storage of 21 TB each but the third host doesn't have local storage except running esxi disk. I will be very grateful if anyone can guide me to which cluster method shall I proceed to. 2 node cluster or 3 node cluster? Does the disk requirement on all the hosts needs to be same.

I will be very grateful for any suggestion.

Thank You

Re: vSAN with 3 node

TheBobkin — Sun, 01 Aug 2021 19:26:54 GMT

@abckdc, in a production cluster, ideally all nodes that are provided storage to the cluster should have the same storage configuration.

Whether you go 2-node or 3-node here depends - a 2-node cluster is comprised of 2 data-nodes + Witness Appliance (that needs to be running somewhere but I guess you could use the excess of the ESXi-install device for VMFS-6 and put it there?), whereas a 3-node cluster is comprised of 3-data nodes, if you only have 2 of them providing storage then FTT=0 is the max failures to tolerate you will be able to apply to the data and thus this will be severely limited in ability to test failures and recovery etc. .

Re: vSAN with 3 node

abckdc — Mon, 02 Aug 2021 03:49:48 GMT

Thank you very much for the reply. So, I can proceed to two node cluster with ftt=1 and set witness appliance on the third host. This third host without storage can reside in the same cluster right or do I have to put it somewhere else (under same vcenter)? If yes can I start machine on this third host(witness) with datastore being vsan. Also, If I need to migrate machine from host 1 to host 3(running witness machine) will it be possible?