Sets the size (MB) for PCMCIA disk1.

        :param disk1: disk1 size (integer)

def set_disk1(self, disk1):
        """
        Sets the size (MB) for PCMCIA disk1.

        :param disk1: disk1 size (integer)
        """

        yield from self._hypervisor.send('vm set_disk1 "{name}" {disk1}'.format(name=self._name, disk1=disk1))

        log.info('Router "{name}" [{id}]: disk1 updated from {old_disk1}MB to {new_disk1}MB'.format(name=self._name,
                                                                                                    id=self._id,
                                                                                                    old_disk1=self._disk1,
                                                                                                    new_disk1=disk1))
        self._disk1 = disk1