Make an RDB backup of the Redis database, use the gsutil utility to copy the RDB file into a Cloud Storage bucket, and then import the RDB file into the Memorystore for Redis instance.

Make a secondary instance of the Redis database on a Compute Engine instance and then perform a live cutover.

Create a Dataflow job to read the Redis database from the on-premises data center and write the data to a Memorystore for Redis instance.

Write a shell script to migrate the Redis data and create a new Memorystore for Redis instance.