def update(self, back=None):
        back = self._gen_back(back)
        for fsb in back:
            fstr = '{0}.update'.format(fsb)
            if fstr in self.servers:
                log.debug('Updating {0} fileserver cache'.format(fsb))
                self.servers[fstr]()
Update all of the enabled fileserver backends which support the update
dataset/ETHPy150Open saltstack/salt/salt/fileserver/__init__.py/Fileserver.update