Upgrading from Drupal 6 or 7 to Drupal 8

Last updated on
1 December 2017

Upgrading a Drupal site means a change of a major version, for example from Drupal 6 to Drupal 8 or from Drupal 7 to Drupal 8. This documentation guide is about upgrading a Drupal 6 or Drupal 7 site to Drupal 8.

Updating a Drupal site means an update from one minor version to another, for example from from '8.0.2' to '8.3.0'. Please refer to Updating Drupal 8 site for more information on updating.

Upgrading to Drupal 8 uses migration approach

Upgrading your site from Drupal 6 / 7 to Drupal 8 uses significantly different approach than previous versions of Drupal. When Drupal 6 site was upgraded to Drupal 7, the same database was upgraded from Drupal 6 structure to Drupal 7 structure as illustrated in the image below. 

Upgrade from Drupal 6 to Drupal 7

When upgrading a Drupal 6 / 7 site to Drupal 8, you first need to install a clean Drupal 8 site. You will then migrate your site configuration and site content to your new Drupal 8 site. Your existing Drupal 6 / 7 site remains completely unaltered and intact.

Upgrading from Drupal 6 / 7 to Drupal 8

Examples of configuration migration: Node content types and the field definitions are configuration entities which can be migrated to Drupal 8 so that you don't need to create them manually in your Drupal 8 site. 

Examples of content migration: The actual nodes, users and taxonomy terms are examples of content entities which can be migrated to Drupal 8 so that you don't need to manually copy-paste the content to your Drupal 8 site.

Although you might hope or expect that your new Drupal 8 site will be essentially the same as your old site, with the added benefit of improved Drupal 8 features, that may not be the case. For example all contributed modules that you need might not have an automatic upgrade path available. Therefore you need to carefully examine the migration results. You might also conclude that it will be easier to manually copy-paste the content from your old site to your new Drupal 8 site or that you want to use a custom migration approach.

Further reading