I have tested a Drupal 7 multi-site before, and it worked for me perfectly. With Drupal 8, it doesn't work as expected.
Suppose there are two sites, site1 with site1_ as table prefix and site2 with site2_ as table prefix.
The documentation says that I should add the following lines in the settings.php file.
'prefix' => array( 'default' => 'site2_', 'users' => 'shared_', ),
It doesn't work because the users table in Drupal 8 doesn't have username and password information.
If I add this lines, Drupal won't work normally too.
'prefix' => array( 'default' => 'site2_', 'users' => 'site1_', 'users_data' => 'site1_', 'users_field_data' => 'site1_', 'user__user_picture' => 'site1_', ),
For example if a user in site1 changes password, this user cannot login with the new password on site2, but the user can login with the old password once, and sign out; then the new password works!
I expected that the migration path from Drupal 6 to Drupal 8 would support migration of the shared table too, but this doesn't seem to be true. Even reading https://www.drupal.org/node/2551549 and https://www.drupal.org/node/2768219 doesn't help me much.
Are shared user tables still supported and working, on Drupal 8?
drush cr all