title: Multicast traffic to Kubernetes
body: <p>I want my pods to receive multicast network traffic flowing from outside of my kubernetes cluster to specific ports in my nodes.</p>
  
  <p>I'm considering two solutions:</p>
  
  <ol>
  <li>Adding <code>hostNetwork: true</code> flag to their <code>yaml</code> file along with <code>hostPort</code> configuration in order to receive the traffic directly to the pod.</li>
  <li>Forwarding the traffic locally on the nodes from <code>eth0</code> interface to <code>docker0</code> interface using <code>iptables</code> command.</li>
  </ol>
  
  <p>Method 1 is an official feature in Kubernetes, but it feels like breaking a security wall that docker originally imposed, and might cause port 
  collisions with host's processes, etc.  </p>
  
  <p>Method 2 on the other hand transparently forwards the multicast network traffic to the pods.<br>
  Despite the fact I can use an automation tool to spread this configuration (ansible/salt etc), anything configured 'out of the scope' of Kubernetes feels a little hacky to me.</p>
  
  <p>Would like to hear your pros and cons, comments, and maybe other solutions to the problem of multicasting to a kubernetes cluster.</p>