Re: What happens existing VDP 6.0 backups if you need to re-deploy the appliance...Can you still recover previously backed up VM's?

I second GS's recommendation. Use VDP's built in replication - much more efficient, more reliable, encrypted, and very flexible (1:1, 1:N, N:1). Replication jobs can also be configured to use a retention policy different than the backup job. For example, you could tell the local VDP appliance to retain daily backup data for 30 days and then replicate that backup data maybe once per week or whatever and retain that replicated backup data for 6 months.