A simple Disk Wipe procedure on Solaris

It's usually a wise precaution to remove sensitive data from disks prior to the disks being transferred from one system to another or discarded on a shelf somewhere. The process is generally referred to as disk sanitising, cleaning, purging, or wiping.

The method you choose to sanitise a disk should depend on the security requirements of your organization.

This article provides a simple procedure to wipe a disk using the purge sub-command from within the Solaris format utility. In essence, the purge commands writes fours patterns to the entire surface of the disk, reads all data and then performs another write.

Procedure

  • As system administrator, run the format utility
    # format
    When prompted, select the disk from the AVAILABLE DISK SELECTIONS
  • Enter the Analyze sub-menu
    format> analyze
    ANALYZE MENU: 
    . . . 
  • Select the purge option
    analyze> purge
    . . . 
  • Once complete, enter quit twice to exit the format utility
    analyze> quit
    format> quit
    #

Final thoughts

Overwriting a disk by using the format command above is usually enough for most purposes, because it greatly reduces the chance that any data can be recovered from the disk. However, any data that remains can potentially be accessed by someone with enough expertise, determination, or money.

To ensure that no one could ever recover data from a disk, you need to degauss or destroy it or keep it in a secure location until the disk is needed again.