func (c *Client) IsOnline() bool {
	return atomic.LoadInt32(&c.connected) == online
}

// LastConn returns when the disk was (re-)connected
func (c *Client) LastConn() time.Time {
	return time.Unix(0, atomic.LoadInt64(&c.lastConn))
}

// LastError returns previous error
func (c *Client) LastError() error {
	c.RLock()
	defer c.RUnlock()