You can use the copy command provided by Cassandra to migrate data.

Step 1: Export data from the source cluster to a CSV file. Connect to the source cluster and execute the following statement in cqlsh:

COPY table_name [( column_list )]
TO 'file_name'[, 'file2_name', ...] ;

After the statement is executed, the data is exported to the file specified in the statement.

Step 2: Import the CSV file to the target cluster and connect to the target cluster. Execute the following statement in cqlsh:

COPY table_name [( column_list )]
FROM 'file_name'[, 'file2_name', ...] ;

After the statement is executed, the data is imported to the target cluster.

Other more convenient methods that allow you to migrate larger volumes of data are being developed and will be available soon. If you have a large amount of data, submit a ticket for technical support.