This read-write integer triggers either loading the device with a specified stored configuration or storing the device's current configuration into that slot, depending on whether it's set to load(1) or store(2). An admin uses this to save a known-good VSAR configuration before making risky changes, or to roll back to one afterward. For example, before testing new ATM stream settings, an admin would set this to store(2) to snapshot the current working configuration first.