Run serverspec script in a jenkins build pipeline

Question

how can i run a serverspec script in a jenkins pipeline? I try this

node {
  stage('serverspec') {
     sh 'rake spec'
  }
}

but then I get the following error:

 Port "8080" should be listening
 Failure/Error: it { should be_listening }
 Errno::ENOTTY:
   Inappropriate ioctl for device

I already to write a kind of wrapper-bash-wrapper which call the $ rake spec command but it don't change the result. I already found out a tutorial in which there a install additional a Rake plugin, but I can't don't under what's the different to a direct call of the test cases Maybe someone here can give me a hint or an short explanation what I am doing wrong. best regards Dan