Drupal 8 core contains the basic migration framework adapted from Drupal 7, but not all of it. The functionality included in Drupal 8 supports upgrading from Drupal 6 and 7 from a database only. There are additional capabilities that are available in contrib:
- Migrate Plus: The Migrate Plus module adds a large part of the Migrate framework functionality. This includes creating migration processes in code and adding Configuration Entities to persist settings to remote systems. It also adds plugins to load data from JSON and XML files.
- Migrate Tools: The Migrate Tools module adds Drush commands to manage migrations. These include running migrations, checking their status and rolling them back as necessary. There is also a UI to view migrations, but as of Drupal 8.1.3, it is not completely functional.
