The system for upgrading Drupal sites has been completely re-written for Drupal 8. The system is largely inspired by the work of the Drupal 7 Migrate and Drupal-to-Drupal Data Migration modules. It is a much more robust and extensible system than in previous major versions of Drupal core.
The functionality of the new Migrate and Migrate Drupal modules greatly expands on the functionality of previous versions of the Migrate module in that they now handle both site configuration and content.
Upgrading from Drupal 6 and Drupal 7 sites is now possible, with support for:
- Drupal 6: core + CCK + Link + Email + Phone + ImageCache modules.
- Drupal 7: only content, users, taxonomy, blocks, menus, filter formats (more coming soon - ).
Migrations that are not yet supported include:
- Views ( )
- Multilingual content ( )
- Node, user, entity references (
Currently, contributed modules are required to run migrations to Drupal 8.
A typical use case of the upgrade process would include installing a new copy of Drupal 8 and running the migration on the Drupal 8 site to migrate configuration and content from the source site. The source site database is not modified during the process.
Migration-Related Modules and Plugins
This Drupal core module provides the underlying API for migrating configuration and content to Drupal 8.
This Drupal core module provides the classes specifically needed to migrate configuration and content from a Drupal site to Drupal 8.
The Drupal Upgrade contributed module provides the tools necessary for performing an upgrade from Drupal 6 or Drupal 7 to Drupal 8 — both a simple user interface (at /upgrade) as well as drush commands. There is on-going work to get the UI moved to Drupal core ( ).
The Migrate Plus contributed module provides optional enhancements, including groups and prepareRow events, to the core Migrate API.
Migrate Tools provides optional drush and UI tools for managing your migrations.
Migration plugins for each core module are located within each module's directory. For example, the migration classes that handle taxonomy vocabularies and terms are located in the core taxonomy module.
Developer documentation is available for writing your own custom migrations.