The transition to configuration entities is a two step process. First, move the migration definition files from the `migrations` folder to a `config/install` folder. Second, rename the files so that they follow this pattern: `migrate_plus.migration.[migration_id].yml`. For example: `migrate_plus.migration.udm_config_json_source_node_local.yml`. And that’s it! Files placed in that directory following that pattern will be synced into Drupal’s active configuration when the module is installed for the first time (only). Note that changes to the files require a new synchronization operation for changes to take effect. Changing the files and rebuilding caches does not update the configuration as it was the case with migrations managed in code.
If you have the Migrate Plus module enabled, it will detect the migrations and you will be able to execute them. You can continue using the Drush commands provided the Migrate Run module. Alternatively, you can install the Migrate Tools module which provides Drush commands for running both types of migrations: code and configuration. Migrate Tools also offers a user interface for executing migrations. This user interface is only for migrations defined as configuration though. It is available at `/admin/structure/migrate`. For now, you can run the migrations using the following Drush command: `drush migrate:import udm_config_json_source_node_local –execute-dependencies`.
Note: For executing migrations in the command line, choose between Migrate Run or Migrate Tools. You pick one or the other, but not both as the commands provided by the two modules have the same name. Another thing to note is that the example uses Drush 9. There were major refactorings between versions 8 and 9 which included changes to the name of the commands.
Read more on 31 days of Drupal migrations website.
