protected function createDatabaseServer(bool $flush = true) : Server
 {
     $cls = $this->container->getParameter('server_class');
     /** @var Server $server */
     $server = new $cls();
     $server->setIdentifier($this->clientServer->getAttribute('id'));
     $server->setOwner($this->clientServer->getOwnerAttribute()->getAttribute('id'));
     $server->setPrefix($this->container->getParameter('prefix'));
     $server->setModules($this->defaultModules($server));
     $this->getManager()->persist($server);
     if ($flush && $this->container->getParameter('database_save_delay') === false) {
         $this->getManager()->flush($server);
     }
     return $server;
 }