*Computer Procedures

Procedures to Sanitize Computers & Storage Media Devices

The most efficient and economical means of sanitizing computers and storage media devices is to overwrite the entire device with zeroes.

In some circumstances it is best to physically destroy the hard drive. Some examples include:

Non-functioning computers

• Non-functioning storage media devices
• Ineffective sanitization process
• Sanitization process is not economically feasible

When physical destruction is used, departments are still responsible for sending the remains to Property Disposition for proper disposal.

Sanitizing

How to sanitize PC hard drives

To sanitize PC hard drives we recommend that departments use either Ontrack DataEraser or Active@ Kill Disk.

Using Ontrack DataEraser

• Purchase and install the DataEraser product.
• Create a self-bootable diskette from ONTRACK menu options.
• Boot up system from diskette.
• Once the software loads, press ENTER to skip welcome screen.
• Select the drive you wish to erase using the arrow keys, press ENTER to confirm your selection.
• When the overview screen comes up, press ENTER to run Data Eraser.
• Select option to do “ENTIRE DRIVE” so that the whole disk and the partition are erased.
• Select the number of passes you wish to use with the arrow keys followed by ENTER to confirm selection.  NOTE: In most instances one pass will sanitize the hard drive.
• Enter the hex pattern to be used on the final overwrite pass, or press ENTER to use the default “00”.  This hex pattern will replace the data on the drive.
• Confirm your choices on the next screen and press ENTER to start erasure process.

Using Active @ Kill Disk

Active@ Kill Disk is available in both a commercial and a free version.  The free version is sufficient to accomplish the policy requirements and carries no time limitation.

Prepare a boot diskette or boot CD by downloading and running the boot disk creator or downloading and burning the ISO image from the Active@ Kill Disk web site.

• Boot the system from the diskette or CD.
• Kill Disk will start automatically and begin to write zeroes to the hard drive.
• When erasing is complete, Kill Disk will terminate.

Sanitizing multiple hard drives in a single computer requires purchase of the commercial Kill Disk product.  Pricing and license terms are available on the Active@ Kill Disk web site.

How to sanitize Macintosh hard drives

• Boot the system from the Mac OS CD.
• Run the Drive Setup Utility under the Utilities folder on your Mac OS CD.
• Start by selecting the hard drive you wish to low-level format.
• Under the Function menu, select Initialization Options.
• Select Low level Format (a check mark will appear) and click OK.
• Click Initialize at the bottom of the main screen.
• Again click Initialize.

How to sanitize other architectures and servers

There are many types of architectures, processors, and operating systems used at the University of Michigan.  No single sanitization method will work on all platforms. Described here are some commonly used platforms and possible sanitization solutions.

Architecture	Operating System	Manufacturer
Sparc	Solaris/Linux	Sun Systems
Alpha AXP	Unix/AIX (Unix Based OS) Linux Windows NT	Digital DEC Hewlett Packard Compaq

Regardless of the architecture, processor, or operating system, most systems utilize standard ATA/IDE or SCSI hard drives.  If a method cannot be devised for sanitizing the machine intact, the hard drives can be removed, connected to a PC with the appropriate disk controller, and sanitized there using Ontrack DataEraser or Active@ Kill Disk.

How to sanitize Sun Systems hard drives

For the Sun Sparc Station “Classics” through the Sparc Station “20’s”, it is recommended that you use the Solaris Operating System CD 7.0 or below.  Then use the Utilities/Tool folder to zero the SCSI hard drive.

Type Boot “cdrom-s”, remember you will need the proper Solaris CD in the CD-ROM.

• At the command prompt type "Format”, then hit enter. You will see something like this: #Format Searching for disks….done.
• Next it will show an available Disk Selection. Example: 0.C0T0D0<ST320413A Cyl 38790 alt 2 hd 16sec 63>/PCI@1F,0/ide@d/dad@0,0.
• Then it will request you to specify disk (enter its number), which is the underlined portion at the start.
• This will bring up the Format Menu
• Type Analyze
• This will bring you to this prompt “Format>analyze”
• Type Purge
• The system will prompt are you sure? Answer Yes
• The system will then make several passes over the disk, overwriting all data contained on the hard drive.

How to sanitize Alpha AXP hard drives

Alpha processors are used in many Digital/DEC, Hewlett Packard, and Compaq systems.  These systems often run Unix-based operating systems such as AIX or Linux. Most Unices include a 'dd' command that can be used to zero a hard drive.  If the operating system install CD or rescue CD is available, boot from it to run 'dd'. Alternatively you may create a boot diskette.

Creating a boot diskette in AIX (3.2x, 3.2.5, or 4.x)

• Prepare a formatted diskette.
• Start the system and script a copy command to create your boot diskette.
  Example: bosboot -d/dev/fd0/ -a

Using 'dd'

• To overwrite a hard drive using 'dd', you must specify its device name.  Examples of IDE hard drive locations under Linux:
• /dev/hda = Primary Master
• /dev/hdb = Primary Slave
• /dev/hdc = Secondary Master
• /dev/hdd = Secondary Slave

• Example: dd if=/dev/zero of=dev/hdx (where x is the IDE device you wish to erase)

• Physical Destruction

Physical destruction should only be used in the following instances:

• When computers or hard drives are inoperable.
• When data tapes such as DDS (Digital Data Storage), DLT (Digital Linear Tape), DAT (Digital Audio Tape), or DC (Data Cartridge) cannot be overwritten through reformatting or initialization.

Destruction Process

• Remove the hard drive, tape, or cartridge from the computer or storage unit.
• Place the device flat or on its side and strike it with a heavy hammer until it is crushed.  Note: Pay particular attention to damaging the platters inside hard drives where data is magnetically recorded.  This type of damage will normally discourage the average person from attempting to recover any data.
• All destroyed hard drives, tapes, and other storage media must be sent to Property Disposition for proper disposal.

Assignment of Responsibility

Instructions for Non-Technical departments or persons sending surplus computers to Property Disposition:

Property Disposition computer consultants will provide assistance and direction to any department/person encountering problems with the sanitization process. Please feel free to contact us by email: ljdixon@umich.edu or by telephone (734) 763-7206.

Property Disposition will provide departments with the option of service level agreements, which are negotiable to sanitize your computers and storage devices on a continuing basis. Contact Steve Sinelli by email: ssinelli@umich.edu or by telephone (734) 763-7303.

*Back to the Computer Preparation Page

Copyright © The Regents of the University of Michigan, Ann Arbor, MI 48109 USA

Feedback or suggestions?

This page was last modified September 25, 2009