In Data ONTAP 7.3 and later, the SnapVault primary and secondary features can be on the same storage system. However, you should enable both the SnapVault primary and the SnapVault secondary licenses on the same storage system.
A storage system licensed as both the SnapVault primary and the SnapVault secondary can send and receive SnapVault backups from other storage systems or locally within itself (for example, between FC and ATA aggregates).