def ActivateInstanceDisks(r, instance, ignore_size=False):
    """
    Activates an instance's disks.

    @type instance: string
    @param instance: Instance name
    @type ignore_size: bool
    @param ignore_size: Whether to ignore recorded size
    @return: job id
    """

    return r.request("put", "/2/instances/%s/activate-disks" % instance,
                     query={"ignore_size": ignore_size})