The nodes create page will redirect you to the locations page if you don't have a location, the concept is the same here (pterodactyl#640)

Author: lancepioch

app/Http/Controllers/Admin/ServersController.php

@@ -226,6 +226,13 @@ public function index()
      */
     public function create()
     {
+        $nodes = $this->nodeRepository->all();
+        if (count($nodes) < 1) {
+            $this->alert->warning(trans('admin/server.alerts.node_required'))->flash();
+
+            return redirect()->route('admin.nodes');
+        }
+
         $services = $this->serviceRepository->getWithOptions();
 
         Javascript::put([

resources/lang/en/admin/server.php

@@ -41,5 +41,6 @@
         'server_reinstalled' => 'This server has been queued for a reinstallation beginning now.',
         'details_updated' => 'Server details have been successfully updated.',
         'docker_image_updated' => 'Successfully changed the default Docker image to use for this server. A reboot is required to apply this change.',
+        'node_required' => 'You must have at least one node configured before you can add a server to this panel.',
     ],
 ];