title: Netty UDP Multicast Not Supported With Epoll. Why?
body: <p>In the class <a href="http://netty.io/4.1/xref/io/netty/channel/epoll/EpollDatagramChannelConfig.html" rel="nofollow noreferrer">EpollDatagramChannelConfig</a>, there are 4 methods that look like this:</p>
  
  <pre><code>@Override
  public EpollDatagramChannelConfig setTimeToLive(int ttl) {
      throw new UnsupportedOperationException("Multicast not supported");
  }
  </code></pre>
  
  <p>These are:</p>
  
  <ul>
  <li><a href="http://netty.io/4.1/xref/io/netty/channel/epoll/EpollDatagramChannelConfig.html#309" rel="nofollow noreferrer">setLoopbackModeDisabled</a></li>
  <li><a href="http://netty.io/4.1/xref/io/netty/channel/epoll/EpollDatagramChannelConfig.html#319" rel="nofollow noreferrer">setTimeToLive</a></li>
  <li><a href="http://netty.io/4.1/xref/io/netty/channel/epoll/EpollDatagramChannelConfig.html#329" rel="nofollow noreferrer">setInterface</a></li>
  <li><a href="http://netty.io/4.1/xref/io/netty/channel/epoll/EpollDatagramChannelConfig.html#339" rel="nofollow noreferrer">setNetworkInterface</a></li>
  </ul>
  
  <p>Is support disabled due to an issue in Netty, or does Epoll simply not support UDP multicast ?</p>
  
  <p>Thanks.</p>