I was trying to migrate from a Windows based vCenter 5.5 install to VCSA 6.5 and after encountering several errors trying to run the migration tool I discovered that I could disconnect and remove a host from vCenter and add it to VCSA without interrupting the VMs.

  1. Spin up new VCSA and recreate EVC clusters. (Make sure to have a DNS A record for VCSA before spinning it up.)
  2. Stop DRS on the vCenter EVC cluster.
  3. Enter maintenance mode for a host. (Don’t evacuate VMs)
  4. Disconnect host from vCenter.
  5. Remove host from vCenter.
  6. Add host to new VCSA.

I lost all the historical performance data, but that’s better than trying to fix SSL certs.

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