HP B6960-90078 Verifying Data on a Medium, When to Verify, How to Verify Data, On a Medium, 128

Managing Media

Verifying Data on a Medium

Verifying Data on a Medium

What Is Verifying? Verifying a medium shows whether the data on the medium is valid. It also updates the information about the medium in the IDB, such as medium condition.

Data Protector performs the following:

•Checks the Data Protector headers with information about the medium (medium ID, description, and location.)

•Reads all blocks on the medium.

•If the CRC (Cyclic Redundancy Check) option was used while writing to the medium, Data Protector recalculates the CRC and compares it to the one stored on the medium.

If the CRC option was not used, and the verify operation passed, this means that all the data on the medium has been read. The medium did not cause a read error, so the hardware status of the tape is at the very least acceptable. This level of check can be viewed as partial.

Additionally, if the CRC option was used, the backup data itself is consistent within each block. This level of check has a high level of reliability.

NOTE	Depending on the backup devices and media you use, this task can take a
	considerable amount of time to complete.
When to Verify	If errors were reported during backup, you can verify the medium to
Media	check whether the backup is usable.
How to Verify Data	In the Devices & Media context, browse for a medium, right-click it, and
on a Medium	click Verify. For detailed steps, refer to the online Help index keyword
	“verifying media”.

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