never use anything else then the VxRail Manager for doing upgrades on VxRail... the VxRail manager is the only guarantee that the software is compatible with the hardware on VXRAIL !

Please refer the KB for VxRail versions and build numbers: KB: https://support.emc.com/kb/494510

I believe if you want to have your ESXi upgraded to 6.5 U2, then VxRail version 4.5.210 should include it. You can refer the KB for each component version and build numbers.

NOTE 1: Please do all components upgrades from VxRail Manager only.

NOTE 2: If it is external VCenter then, VxRail Upgrade workflow will not upgrade VCenter, the customer should plan for his Vcenter upgrade to match the VxRail code level before performing VxRail upgrade.

For upgrade procedure, you can refer to SolvE desktop. If any doubts or assistance required, please open a Support request.

When ever working on VxRail, you should always refer tot he SolVe Procedure Generator. SolVe is available in an Offline desktop executable or an Online version with no download required. SolVe is available to all Dell EMC Badged employees, Service enabled partners and registered customers.  Access is based on your support account profile.

The URL is: https://solveonline.emc.com/solve/products

Select your product, in this case VxRail.  All procedures are available by selecting from the menu's.

Never attempt to perform a software upgrade on VxRail outside of VxRail Manager. As all software updates are provided from the VxRail Product group, are fully tested and qualified for VxRail hardware.