A network slice controller obtains health information of an active network slice provided by a first vendor and health information of a set of backup network slices provided by a second vendor. The network slice controller evaluates, using a set of policies corresponding to management of the active network slice, the health information of the active network slice to determine whether the active network slice has failed. As a result of the failure of the active network slice, the network slice controller identifies one or more backup network slices of the set of backup network slices to serve as new active network slices. The network slice controller activates these one or more backup network slices to serve as the new active network slices for the network.