VSAN VM pinned to site - what happens during disk / diskgroup failure

[anandgopinath]

Dear Community 

 We have a stretched cluster  with 2 Data nodes  ( one in each site  )  + witness as below.

We have 2 disk groups per host . all flash .  no storage efficiency or encryption . 

For VMs pinned to each site  (  Site disaster tolerance None - keep data on Secondary (stretched cluster) / Failures to tolerate No data redundancy ) 

will we loose a VM  for ever  ( recoverable only from backups )  in case of a  cache disk / capacity disk or full disk group failure  ? 

as per the stretched cluster guide , it says vm will survive a disk or diskgroup failure by moving data to the other disk group , disks  . is this true  ? 

i am lost  .

appreciate your quick response  . 

Site disaster tolerance None - keep data on Preferred (stretched cluster)
Failures to tolerate No data redundancy

[TheBobkin · Accepted solution]

@anandgopinath 

"will we loose a VM  for ever  ( recoverable only from backups )  in case of a  cache disk / capacity disk or full disk group failure  ? "

Yes, as you have just lost the only copy of the data.

"as per the stretched cluster guide , it says vm will survive a disk or diskgroup failure by moving data to the other disk group , disks  . is this true"

How would it move anything? The only replica is gone, there is nothing to read from.

What you read was likely referring to PFTT=1 or SFTT=1 data where there was still available replica and somewhere valid to recreate second replica replacing the lost one.