code: def update(self):
          
          if self.client_mode == 'glances':
              return self.update_glances()
          elif self.client_mode == 'snmp':
              return self.update_snmp()
          else:
              self.end()
              logger.critical("Unknown server mode: {}".format(self.client_mode))
              sys.exit(2)
docs: Update stats from Glances/SNMP server.