Rollback Plan while upgrading from vcenter 5.5.U3 to 6.5 U2 VCSA

[ankitrtr]

I want to know the exact measures that I need to take while migrating from vcenter server  from 5.5 U3 to 6.5 U2. How can I take backup of the current vcenter server? Do i need to take backup of the current vcenter database server? Just taking a snapshot of the vcenter will ensure full backup? What are the steps that I need to do if my migration from vcenter server on windows to the appliance fails?

[RickVerstegen]

Have a look at these articles for upgrade planning to 6.5:

VMware Knowledge Base

https://vspherecentral.vmware.com/path-finder/vsphere-6-5-topology-and-upgrade-planning-tool-1

https://www.starwindsoftware.com/blog/vmware-vsphere-6-5-what-to-be-aware-of-before-upgrade