code: public IpcLogEntry withServerAsg(String asg) {
      this.serverAsg = asg;
      if (serverApp == null || serverCluster == null) {
        ServerGroup group = ServerGroup.parse(asg);
        serverApp = (serverApp == null) ? group.app() : serverApp;
        serverCluster = (serverCluster == null) ? group.cluster() : serverCluster;
      }
      return this;
    }
docs: Set the server ASG for the request. In the case of the client side this will be
  automatically filled in if the {@link NetflixHeader#ASG} is specified on the server
  response. The ASG value must follow the
  <a href="https://github.com/Netflix/iep/tree/master/iep-nflxenv#server-group-settings">
  Frigga server group</a> naming conventions.