grow_and_shrink (GrowShrinkStrategyConfig)
A simple strategy that creates new instances with the new plan, migrates data across from the old instances, and then shuts down the old instances - it is safer than 'rolling' and ensures single node availability during a plan change, but can be a lot slower on larger clusters
rolling (RollingStrategyConfig)
Allows for performing many configuration changes in-line in a rolling manner, mutating existing containers.It is the fastest way of updating a plan, but may fail for more complex plan changes (eg topology changes) and is less safe for eg configuration changes that can leave a cluster in a non-running state. Note that rolling (with 'group_by' set to '__all__') is required when performing a major version upgrade