Vxrail VSAN datastore Migrate to PMAX datastore NOT exact storage usage after migrated.

VxRail use VMware vSAN and based on your policy and your FTT Settings its vSphere which is responsible for the "protection". When having FTT=1 and RAID1 your vSphere needs AND counts every vDisk*2 because of the RAID1 which means that is needs a copy of the object for surving a failure. A 100G vDisk neeeds 100GB and aditional 100GBfor the copy of the space which mean around 200GB in total and this is what is display in the GUI as "Storage".
If your 100G is a thinprovisioning one and the OS only consumed 60GB for example your vSphere needs 2*60GB but the OS see 1x100. So in real life its not exactly a 2:1 ratio.

When speaking of vSphere and your PMAX SAN its not the responsible of vSphere anymore when it comes for protection and redundancy... so a 100GB VM needs 100GB disk usage on your SAN (in theorie) and thats what the vSphere GUI will tell how.  Now the PMAX providing the protection with a RAID 5/6 or what ever and vSphere doesnt calculate that space for you.

Regards,
Joerg

Hi Joerg,

Thanks for your response, Please confirm this is normal when we migrated from vSAN to SAN it will be reduced storage after vMotion without encountering files being deleted.

Thank you!

Je- M