For the virtual network embedding in Software Defined Network (SDN), the existing researchers mainly consider the acceptance rate, but ignore the problem of the underlying resource failure in SDN. Aiming at the problem of Survivable Virtual Network Embedding (SVNE) in SDN, a virtual network embedding guarantee mechanism was proposed combining priori protection and posteriori recovery. Firstly, the regional resources of SDN physical network were perceived before a virtual request was accepted. Secondly, the backup physical resources for the virtual network elements with relatively reduced remaining resources in the mapping domain were reserved by the priori protection mechanism, and the extended virtual network was embedded into the physical network by the D-ViNE (Deterministic Virtual Network Embedding) algorithm. Finally, when a network element without reserved backup resources was out of order, the fault was recovered by the posterior recovery algorithm, which means the node and the link were recovered by remapping and rerouting respectively. Experimental results show that compared with the SDN-Survivability Virtual Network Embedding algorithm (SDN-SVNE), the proposed mechanism has the virtual request acceptance rate increased by 21.9%. And this protection mechanism has advantages in terms such as virtual level fault recovery rate and physical level fault recovery rate.