This is a very simple example that does not account for the possible existence of folders, uppercase characters, or numerals. The first instance of the command copies all files that do not begin with the lowercase letters a–n, and the second instance of the command copies all files that do not begin with the lowercase letters o–z. When using this method, double check your exclude parameters to avoid conflicts caused by both instances performing operations on the same files.

To take advantage of additional threads, restrict the scope of the --exclude filter for each instance of the AWS CLI that you run. The same technique can be used to move or synchronize files between source and destination buckets. The use of multiple threads can significantly increase data throughput. Additionally, these commands support a local directory as a source or destination, so you can copy, move, or synchronize files to or from your local computer to an Amazon S3 bucket.

One drawback to this approach is the possibility of slowdowns caused when making multiple requests to S3 for sequential key/file names. For more information about this potential pitfall, see Request Rate and Performance Considerations.