ESXi 6.5 update2 with different VMFS on 2 equal servers

Hi there,

I have installed ESXi 6.5 update2 on 2 equal Cisco UCS M3 (UCSC-C220-M3SBE) with the same exact hardware configuration and same disks model/configuration but I see on server 2 that the installation have formatted the datastore1 with VMFS5 instead of VMFS6. Installation on server1 is correct with datastore1 formatted with VMFS6.

I have read in regards of the different VMFS depending on the disks version 512n or 512e but I do not understand why 2 exact servers are being installed with a different VMFS.

The only difference I have noted is the bios version on both servers:

Server1: C220M3.2.0.1b.0 (Build Date: 05/26/2014) --> Installed with default VMFS6

Server2: C220M3.2.0.3.0 (Build Date: 08/01/2014) --> Installed with default VMFS5

Any of you have encountered the same issue as mine and got a clarification from VMware?

Thank you!

Gabri