def _osd_pct_used(self, health):
        """Take a single health check string, return (OSD name, percentage used)"""
        # Full string looks like: osd.2 is full at 95%
        # Near full string: osd.1 is near full at 94%
        pct = re.compile(r'\d+%').findall(health)
        osd = re.compile(r'osd.\d+').findall(health)
        if len(pct) > 0 and len(osd) > 0:
            return osd[0], int(pct[0][:-1])
        else:
            return None, None