Skip to main content

Sanitizing a disk in maintenance mode

Beginning in ONTAP 9.6, you can perform disk sanitization in maintenance mode. This allows you to remove data from a disk or a set of disks on decommissioned or inoperable systems so that the data can never be recovered.

Before you begin

  • The disk cannot be a self-encrypting disk (SED).

    You must use the storage encryption disk sanitize command to sanitize an SED.

    Encryption of data at rest

  1. Boot into maintenance mode.
  2. If the disks you want to sanitize are partitioned, unpartition each disk:disk unpartition disk_name
  3. Sanitize the specified disks: disk sanitize start [-p pattern1|-r [-p pattern2|-r [-p pattern3|-r]]] [-c cycle_count] disk_list

    Attention
    Do not turn off power to the node, disrupt the storage connectivity, or remove target disks while sanitizing. If sanitizing is interrupted during the formatting phase, the formatting phase must be restarted and allowed to finish before the disks are sanitized and ready to be returned to the spare pool.

    If you need to abort the sanitization process, you can do so by using the disk sanitize abort command. If the specified disks are undergoing the formatting phase of sanitization, the abort does not occur until the phase is complete.

    -p pattern1 -p pattern2 -p pattern3 specifies a cycle of one to three user-defined hex byte overwrite patterns that can be applied in succession to the disks being sanitized. The default pattern is three passes, using 0x55 for the first pass, 0xaa for the second pass, and 0x3c for the third pass.

    -r replaces a patterned overwrite with a random overwrite for any or all of the passes.

    -c cycle_count specifies the number of times that the specified overwrite patterns are applied. The default value is one cycle. The maximum value is seven cycles.

    disk_list specifies a space-separated list of the IDs of the spare disks to be sanitized.

  4. If desired, check the status of the disk sanitization process: disk sanitize status [disk_list]
  5. After the sanitization process is complete, return the disks to spare status by entering the following command for each disk: disk sanitize release disk_name
  6. Exit maintenance mode.