// the Service reference is required.
func (a *Allocator) AllocateNext() (net.IP, error) {
	return a.AllocateNextService(nil)
}

// AllocateNext return an IP address that wasn't allocated yet.
func (a *Allocator) AllocateNextService(svc *api.Service) (net.IP, error) {
	return a.allocateNextService(svc, dryRunFalse)
}

// allocateNextService tries to allocate a free IP address within the subnet.

}

func (c *MetaAllocator) Allocate(ip net.IP) error {
	allocator, err := c.getAllocator(ip)
	if err != nil {
		return err
	}
	return allocator.Allocate(ip)
}

func (c *MetaAllocator) AllocateNextService(service *api.Service) (net.IP, error) {
	c.muTree.Lock()
	defer c.muTree.Unlock()

	// TODO(aojea) add strategy to return a random allocator but

				// TODO: simplify this and avoid all this duplicate code
				svcAllocator, ok := allocator.(*ipallocator.MetaAllocator)
				if ok {
					allocatedIP, err = svcAllocator.AllocateNextService(service)
				} else {
					allocatedIP, err = allocator.AllocateNext()
				}
			} else {
				allocatedIP, err = allocator.AllocateNext()
			}
			if err != nil {