NetApp Disk Sanitization

WHAT IS DISK SANITIZATION?

Disk sanitization is the process of obliterating stored data by means of overwriting patterns on NetApp system drives in a manner that prevents recovery of that data by any known recovery methods. The process consists of a drive format operation followed by the specified overwrite patterns repeated for the specified number of cycles. For SATA drives, the drive format operation is skipped because the SCSI format command is not supported on these drives.

DO I NEED A LICENSE TO RUN DISK SANITIZATION? HOW MUCH DOES IT COST?

A license is required to run disk sanitization; however, the license is free.

IS DISK SANITIZATION SUPPORTED IN DATA ONTAP OPERATING IN CLUSTER-MODE?

Yes. Data ONTAP operating in Cluster-Mode does include the disk sanitization feature.

WHY WOULD I WANT TO SANITIZE A DISK?

There are several reasons to sanitize a drive. For example, compliance or security protocols might require that drives that have been used to store sensitive data undergo a process that guarantees that the sensitive

data is not recoverable from the drive. Perhaps drives are being repurposed for a different system and need to be sanitized before being deployed. Whatever the reason, once a drive is sanitized, the data is not recoverable.

HOW DO I KNOW IF DISK SANITIZATION IS SUPPORTED ON A PARTICULAR DRIVE?

To determine whether disk sanitization is supported on a specific drive, run the storage show disk

command. If the vendor of the drive in question is listed as NetApp, then drive sanitization is supported. Disk sanitization support was introduced in Data ONTAP 8.1.1 for the NetApp 100GB SSD drive, X441A.

WHAT SECTORS OR DATA DOES DISK SANITIZATION OVERWRITE?

Disk sanitization overwrites the entire contents of the drive.

HOW DOES SANITIZATION DIFFER FROM STANDARD ZEROING?

With sanitization, any pattern can be written, including all zeroes. Random patterns can also be written. Zeroing a drive clears only the file data areas; it does not clear the entire drive.

HOW ARE BAD BLOCKS AFFECTED BY DISK SANITIZATION?

Bad blocks are removed from the grown defect list during formatting. If the bad block can be written to, then it is also sanitized.

WHAT ARE THE DIFFERENCES, IF ANY, BETWEEN FC/SAS AND SATA DISK SANITIZATION?

For SATA drives, the drive format operation is skipped because the SCSI format command is not supported.

IS IT ADVISABLE TO BYPASS THE FORMAT OPERATION ON FC/SAS DRIVES?

Yes. There is no real advantage to the format operation if there are no grown defects.

CAN YOU SANITIZE INDIVIDUAL FLEXVOL VOLUMES, LUNS, OR FILES?

No. You can only sanitize individual drives.