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Step 6: On page ‘Drupal Upgrade’ you will see connection options to the legacy database. If Drupal 8 can’t connect to the legacy base, you will see error. Fox example: ‘SQLSTATE[HY000] [1049] Unknown database 'drupal7_'’. Check your settings.php file and try to fix options.
Do not forget input correct path to your legacy Drupal 7 site for files migration.
For Example: /var/www/drupal7
Click on button ‘Review upgrade’
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