### Cassandra Cluster Setup and Data Migration Workflow

Workflow for setting up a Cassandra cluster with multiple nodes, creating keyspaces and schemas, and exporting and reimporting data. The process ensures synchronization across nodes and efficient data migration using snapshots.

#### Workflow Phases
The workflow is divided into the following phases:
1. **Startup Phase**: All nodes start Cassandra and ensure they are ready to accept connections.
2. **Schema Creation Phase**: The primary node creates the keyspace and schema if they do not exist. This schema is then propagated to other nodes.
3. **Data Import Phase**: Data is imported from snapshots using `sstableloader` only if the schema was newly created.

#### Phase 1: Startup Phase
Each node starts Cassandra and waits for it to be ready before proceeding to the next phase.

- **Primary Node**: Starts Cassandra and waits for other nodes to signal they are ready.
- **Non-Primary Nodes**: Wait for the primary node to be ready before starting Cassandra.

#### Phase 2: Schema Creation Phase
After all nodes are confirmed to be ready, the primary node checks if the keyspace exists and creates it if it does not.

- **Primary Node**:
  - Checks if the keyspace exists.
  - If the keyspace does not exist, creates the keyspace and applies the schema.
  - Waits for the schema to propagate to all nodes.
- **Non-Primary Nodes**:
  - Wait for the primary node to complete schema creation and propagation.

#### Phase 3: Data Import Phase
Data is imported into the keyspace using `sstableloader` from the snapshots if the schema was newly created.

- **Primary Node**:
  - If the schema was created, imports data from the snapshots.
- **Non-Primary Nodes**:
  - Wait for the primary node to complete the data import.