Disk Safe Verification

*Disk Safe Verification* (DSV) provides added integrity assurance through block-level verification of stored data against its source. The verification process is targeted at detecting and alerting the user in the event of any possible corruption in a Disk Safe. Using Disk Safe Verification, you can be sure that your Disk Safes remain intact and ready for any data restore requests. Disk Safe Verification runs on *a separate schedule* for each Policy to occasionally inspect the Disk Safe for any signs of corruption. 

Once the Disk Safe Verification procedure has started, you will see DSV tasks in the [task history|Task History]. The default DSV schedules should be appropriate for most users. However, in some cases, DSV tasks need to be run more or less frequently depending on factors that may include the following:
* How busy the Backup Manager server is (i.e. how many servers it is backing up)
* How important it is to ensure that no possible corruption has taken place

When run, DSV will hash and compare block data in the Disk Safe to the hashes that were stored for the block data when written to the Disk Safe. If the hashes no longer match, the data has been altered/corrupted, and an alert will be created in the Policy to inform the user. If a Disk Safe Verification task detects corruption, the Backup Agent will run a full block scan to verify every possible changed block and will send back any changed blocks. This will ensure that there is a full, consistent Recovery Point in the Disk Safe after the very next backup following the detection of an issue in the Disk Safe.