diff --git a/core/modules/migrate/tests/src/Kernel/HighWaterTest.php b/core/modules/migrate/tests/src/Kernel/HighWaterTest.php
index 26cc7dcd3f..e2198cf407 100644
--- a/core/modules/migrate/tests/src/Kernel/HighWaterTest.php
+++ b/core/modules/migrate/tests/src/Kernel/HighWaterTest.php
@@ -81,6 +81,20 @@ protected function setUp(): void {
     $this->executeMigration('high_water_test');
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  protected function prepareMigration(MigrationInterface $migration) {
+    // Simulate that the source and destination DB are on different hosts and
+    // are hence not joinable.
+    // @see \Drupal\migrate\Plugin\migrate\source\SqlBase::mapJoinable()
+    $source = $migration->getSourceConfiguration();
+    if ($source['plugin'] === 'high_water_test') {
+      $source['ignore_map'] = TRUE;
+      $migration->set('source', $source);
+    }
+  }
+
   /**
    * Tests high water property of SqlBase.
    */