private void normalizeHosts(SshHostInfo info) {
    List<String> validHosts = new ArrayList<>();
    List<String> newHosts = new ArrayList<>();
    
    for (String host: info.getHosts()) {
      try {
        InetAddress addr = InetAddress.getByName(host);
        
        if (!validHosts.contains(addr.getHostAddress())) {
          validHosts.add(addr.getHostAddress());
          newHosts.add(host);
        } else {
          LOG.warn("Host " + host + " has already been targeted to be bootstrapped.");
        }
      } catch (UnknownHostException e) {
        LOG.warn("Host " + host + " cannot be determined.");
      }
    }
    
    info.setHosts(newHosts);
  }
Gets a list of bootstrapped hosts.

@param info  the host info, with no SSL key information required
ambari-server/src/main/java/org/apache/ambari/server/api/rest/BootStrapResource.java