- 1. If the system is preinstalled with UFM module vSphere 6.0 can we just download 6.5 from the vendor and run the upgrade from DVD
yes you can, but before check if hardware does support to vSphere 6.5
2. If the system is not preinstalled, and the UFM module is empty, can we download 6.5 install this with the license we have for 6.0 ?
yes , vSphere 6.5 product does not need new license keys. The existing 6.0 licenses will work and enable all the features of the software once upgraded. The ESXi 6.5 features are automatically enabled after you upgrade from ESXi 6.0.
All vSphere 6.x and vCenter Server 6.x keys work with ESXi 6.5 and vCenter Server 6.5. Prior to upgrading your software from 6.0 to 6.5 please view Important information before upgrading to vSphere 6.5 (2147548)
See below link for vcenter upgrade from 6.0 to 6.5 and many more ........
http://masteringvmware.com/how-to-upgrade-vcenter-server-6-to-vcenter-server-6-5-step-by-step/
Regards,
Randhir
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