@classmethod
def backend_add(cls, name, backend):
    """ Add a backend into a webaccelerator """
    oper = cls.call('hosting.rproxy.server.create', cls.usable_id(name),
        backend)
    cls.echo('Adding backend %s:%s into webaccelerator' % (backend['ip'],
        backend['port']))
    cls.display_progress(oper)
    cls.echo('Backend added')
    return oper
