Keep cluster running until cut-over noted below.

Pull an existing, old compute node from Lancaster's cluster and convert it into a new head node.

Install new OS

Add a new compute node (from Crane) to this new head node.

Pull another existing, old compute node from Lancaster's cluster and test it mounts to new head node.

Test new head node with 2 new compute nodes (from Crane), and old compute node

Cut-over accounts and data from old compute node to new compute node.

Move the rest of Lancaster's old compute nodes to the new head node.

Confirm all is working.

Convert old head node into a compute node.