defer config.RUnlock()
	_, valid := config.isTierNameInUse(tierName)
	return valid
}

// isTierNameInUse returns tier type and true if there exists a remote tier by
// name tierName, otherwise returns madmin.Unsupported and false. N B this
// function is meant for internal use, where the caller is expected to take
// appropriate locks.
func (config *TierConfigMgr) isTierNameInUse(tierName string) (madmin.TierType, bool) {