if err != nil {
		logger.Fatal(fmt.Errorf("invalid arguments passed, private key file is not accessible: %v", err), "unable to start SFTP server")
	}

	private, err := ssh.ParsePrivateKey(privateBytes)
	if err != nil {
		logger.Fatal(fmt.Errorf("invalid arguments passed, private key file is not parseable: %v", err), "unable to start SFTP server")
	}

	if userCaKeyFile != "" {