func (s *ProxyServer) setupConntrack(ctx context.Context) error {
	ct := &realConntracker{}

	max, err := getConntrackMax(ctx, s.Config.Conntrack)
	if err != nil {
		return err
	}
	if max > 0 {
		err := ct.SetMax(ctx, max)
		if err != nil {
			if err != errReadOnlySysFS {
				return err
			}
			// errReadOnlySysFS is caused by a known docker issue (https://github.com/docker/docker/issues/24000),