Table of ContentsView in Frames

Disk sanitization process

Understanding the basics of the disk sanitization process helps you understand what to anticipate during the sanitization process and after it is complete.

The disk sanitization process uses three successive default or user-specified byte overwrite patterns for up to seven cycles per operation. The random overwrite pattern is repeated for each cycle.

Depending on the disk capacity, the patterns, and the number of cycles, the process can take several hours. Sanitization runs in the background. You can start, stop, and display the status of the sanitization process.

The sanitization process contains two phases:

  1. Formatting phase
    • For capacity HDDs (SATA, BSAS, FSAS, MSATA, or ATA) the formatting phase is skipped.
    • For performance HDDs (SAS or FC), the formatting phase consists of a SCSI format operation.
    • For SSDs, the formatting phase consists of a SCSI sanitize operation.
  2. Pattern overwrite phase

    The specified overwrite patterns are repeated for the specified number of cycles.

When the sanitization process is complete, the specified disks are in a sanitized state. They are not returned to spare status automatically. You must return the sanitized disks to the spare pool before the newly sanitized disks are available to be added to another aggregate.