functional/agent/handler.go
func (srv *Server) createEtcdLogFile() error {
	var err error
	srv.etcdLogFile, err = os.Create(srv.Member.Etcd.LogOutputs[0])
	if err != nil {
		return err
	}
	srv.lg.Info("created etcd log file", zap.String("path", srv.Member.Etcd.LogOutputs[0]))
	return nil
}
func (srv *Server) createEtcdLogFile() error {
	var err error
	srv.etcdLogFile, err = os.Create(srv.Member.Etcd.LogOutputs[0])
	if err != nil {
		return err
	}
	srv.lg.Info("created etcd log file", zap.String("path", srv.Member.Etcd.LogOutputs[0]))
	return nil
}
// just archive the first file