Safe, Secure and Polite Macin’ — Things You Should Practice

How to Completely Erase the Hard Disk — Tips to Avoid Data Theft When Donating a Computer System {Even to your kids}

A new column by Harry {doc} Babad     © 2009

 

 

As I occasionally go through my old files, including downloaded or scanned magazine columns. I usually find, around the 20^th of the month the macC article due date, some fine archived articles many that are as fresh as they were 3-7 years ago.  The Macintosh moves on — focus areas change. We’re finally starting to get some respect from the PC community, members of which are either switching of dual platform using their computers. I’ve recently spent a little time talking with friends who’ve taken the PC to Mac plunge or new users.  I found they had very little concept of how to compute responsibly, efficiently and safety. The PC users were to busy staying alive and keeping ahead on their tasks to care. And the newbies were… Therefore, this column.

 

Acknowledgements: Unless otherwise noted I have provided the source of the material in these articles. I also found materials in the many notes I’ve stashed for future articles, that certain themes keep coming up, that parallel what I’ve read or practiced.  In most cases I have acknowledged as well as significantly modified the original document(s) to personalize them for our readers. It’s called research as long as credit is given where it’s due.

 

Introduction

 

Perhaps you have decided to forgo system upgrades and get rid of your computer system and purchase a new one. Although focused on a newer oldie that can use OS X, the suggestions also makes sense for a real oldie — as long as you tell the beneficiary of your classic Macintosh its limitations. Alternatively, you’re in a pass down mode but don’t want to spend the time clearing out your sensitive files, obscure shareware or your highly customized software that no one else can figure out.  All of this before your sister-in-law or teenage son, the beginning gamer, inherits.  After all, that older but perfectly good Macintosh is still a good productivity machine for most users and alas worth very little when sold. …And you did add a larger hard drive, max it out on memory and kept, up to this point, all your systems software up to date.

 

They Say Charity Begins at Home — However, if you’ve decided to donate your old computer to a charity, local group or school, it’s important to make sure your computer’s hard drive is completely free of data.

 

In the no good deed ever goes unpunished department, you need to ensure that you don’t donate more than you planned. The last thing you want to do is to pass on a computer containing sensitive business information, your ‘secrete” love letters, or even personal information such as stored passwords, personal documents, and credit card numbers. All of this information and more you’ve forgotten about can be retrieved and used to harm you.

 

When you donate a computer, you really don’t know where it may end up, or if it will go through the hands of a malicious person with the capability to restore previously recorded and deleted data. You did know that simply deleting information (Command-T) only erases the address of that material so the finder and spotlight ignore it. The trashed file, or parts of it remain on you hard drive until it gets overwritten with new material.

 

There are many ways to go about ensuring your data can never be retrieved. Obviously, you can choose to physically smash the drive, but there are alternatives that enable you to keep the system intact so you can donate a complete system a computer and its OS.

 

First some definitions so you can talk the talk before you try to walk the walk.

 

Key Terms To Understanding Disk Wiping

 

Disk Formatting — “The process of preparing a hard disk or other storage medium for use, including setting up an empty file system. When you format a disk, the operating system erases all bookkeeping (addressing) information on the disk, tests the disk to make sure all sectors are reliable, marks bad sectors (that is, those that are scratched or otherwise damaged), and creates internal address tables that it later uses to locate information.

 

“Large disks can be partitioned, that is, divided into distinct sections that are formatted with their own individual file systems. This is normally only done on hard disks because of the small sizes of other disk types, as well as compatibility issues.

 

“A corrupted operating system can be reverted to a clean state by formatting the disk and reinstalling the OS, as a drastic way of combating a software problem or malware infection. Obviously, important files should be backed up beforehand.”

 

{Wikipedia} If you’re getting rid of the computer, and want to keep your data, backups become even more essential. You really don’t want to loose those passwords, financial records, bank account numbers, social security numbers and tax records. And hmm… those love letters.

Hard Drive — A hard disk drive (HDD), commonly referred to, as a hard drive, hard disk, or fixed disk drive, is a non-volatile storage device, which stores digitally encoded data on rapidly rotating platters with magnetic surfaces (e.g., its platter). Strictly speaking, "drive" refers to a device distinct from its medium, such as a tape drive and its tape, or a floppy disk drive and its floppy disk.

 

Early HDDs had removable media; however, an HDD today is typically a sealed unit (except for a filtered vent hole to equalize air pressure) with fixed media.

 

{Wikipedia} We now even have a better, but more expensive storage called a solid-state memory drive, which has no moving parts, for enhanced durability. Never the less whether its an external drive, or a built in one, the concepts remains that it’s the place your computer stored the data and applications you use.

 

Okay Down to Business — Sterilize that Hard Drive or at Least it’s Data

 

Erasing and Reformatting — Simply >erasing (trashing) all the data on your hard drive or formatting it is not enough security. You could spend hours going through your hard drive and deleting all the files and documents you don’t want to share with the computers new owner. Don’t, that does not protect you. Trashing a file or application basically only removes the shortcuts to the files, making them invisible to casual users.

 

Deleted files still lives and hides on your hard drive. Indeed there are many services available that will recover data; most of it from a really trashed (e.g., Katrina soaked) hard drive but are very pricy. But that is not our objective — I got carried away.

 

However the software tools provided by Apple for free, or third party developers do an excellent job of assuring trashed information stays trashed.

 

 

Checking your favorite software supplier or doing a quick Google search will identify many software tools for trashed file recovery will allow anyone to restore that data. You can even read the reviews on both how well they work and their ease of use. Why-Who Needs It? Oh you accidentally trashed that term paper or the draft of your new book you were working against the clock to complete. Your backups our out of date, so where do you turn? Hard disk recovery tools of course. The same tool gave the capability to bulletproof your drive that even a supper computer will have trouble getting at your data.

 

Caveat: this works only if the data has not been over-written. This statement, as you’ll se later is not completely true, but is valid if you overwrite all the data many times. But then you system is also dead and gone. Is there a middle ground — read on!

 

Reformatting the hard drive is a bit more secure than simply erasing the files. Formatting a disk does not erase the data on the disk, only the address tables. It makes it much more difficult to recover the files. However a computer specialist would be able to recover most or all the data that was on the disk before the reformat.

 

For those who accidentally reformat a hard disk, being able to recover most or all the data that was on the disk is a good thing. However, if you’re preparing a system for retirement to a charity or other organization, this obviously makes you more vulnerable to data theft.

 

For some individual users and businesses, a disk format may be something you consider secure enough depending, of course, on the type of data and information you saved to your computer. As long as people understand that formatting is not a 100 percent secure way to completely remove all data from your computer, then they are able to make the choice between formatting and even more secure methods. If you have decided a disk format is a good choice, at the very least you should do a full format rather than a quick format.

 

Disk Wiping Options (aka a Data Dump)

 

Disk wiping is an even more secure process than reformatting. The term “disk wiping” is not only used in reference to hard drives but any storage device such as CDs, RAIDs, thumb drives, and others. Disk wiping is a secure method of ensuring that data, including company and individually licensed software on your computer and storage devices, is irrecoverably deleted before recycling or donating the equipment.

 

Because previously stored data can be brought back with the right software and applications, the disk wiping process will actually overwrite your entire hard drive several times with data. Once you wipe your disk, you will find it all but impossible to retrieve the data that was on the drive before doing so.

 

While disk-wiping algorithms differ from product to product, they all will generally write the entire disk with a number (zero or one), then reformat the disk. The more times the disk is overwritten and formatted, the more secure the disk wipe is, but the trade-off is the extra time to perform additional rewrites. Disk wipe applications will typically overwrite the master boot record, partition table, and every sector of the hard drive.

 

The government standard (DoD 5220.22-M), considered a medium security level, specifies three full iterations to completely overwrite a hard drive. Each iteration makes two write-passes over the entire drive; the first pass inscribes ones (1) over the drive surface and the second inscribes zeros (0) onto the surface. After the third iteration, a government-designated code of 246 is written across the drive, and then it is verified by a final pass that uses a read-verify process.

 

There are a variety of products available for different operating systems that you can purchase or freely downloaded online to perform more secure disk wipes. If time to perform the disk wipe is a consideration, there are also tech security companies who offer disk wipe services.

 

Did You Know? In 2003 two MIT students purchased 158 used disk drives from various locations and found more than 5,000 credit card numbers, medical reports, detailed personal and corporate financial information, and several gigabytes worth of personal email and pornography on those drives.

 

Drive Genius 2.1.x

 

The only product I know enough to share is Drive Genius. My pre OS X favorite a Norton Product was discontinued.

Requirements: Mac OS X 10.2 or higher. Shareware $99

Drive Genius is an OS X utility designed to provide storage management. Featuring an easy-to-use interface, Drive Genius is packed with powerful tools such as a drive optimizer, a comprehensive repair facility for analyzing, repairing and rebuilding volumes, plus excellent testing capabilities with media surface scanning, performance benchmarking and data integrity checking. It can be used to initialize drives, create and delete partitions, and erases them securely as per Department of Defenses standard.

 

Hard Drive Erasing

 

To erase a Macintosh hard drive, boot with a Mac OS X install CD and use the Disk Utility on the drive. Apple Tech Note 107437 gives this procedure for Mac OS X Systems:

 

Note: This refers to a full Mac OS X 10.4.9 or later CD included with a computer, not to the update-only 10.2.3 CD. However the software is available to work with older OX X systems from Prosoft Engineering, its developer.

 

Steps for Zeroing Data Using Apples Disk Utility Software

 

Note to erase your boot volume you must mount the Disk Utility containing disk, since the software can not erase its on operating system.

These steps assume you have a Mac OS X 10.2.3 or later CD:

 

1. Insert the Mac OS X CD.
2. Restart the computer.
3. Immediately after the startup sound, press and hold the “C” key to start up from CD.
4. When the Installer screen appears, do not click “Continue.” Instead, choose “Installer > Open Disk Utilities.”
5. Select the hard drive to erase.
6. Click the “Erase” tab.
7. Select the volume format from the “Volume Format” pop-up menu.
8. Click “Options.”
9. Select the checkbox for “Zero all data.”
10. Click “OK.”
11. Erase.

For a more secure method of erasing of data, you can select the checkbox “8 Way Random Write Format” instead of or in addition to selecting “Zero all data.” This process could take several hours.

 

For those wanting to “Clean” individual files, note this section from Apple’s technical note: Secure Empty Trash You can securely empty the Trash in Mac OS X. While in the Finder, from the File menu choose “Secure Empty Trash.”

 

Note: When you securely empty the Trash, the deleted data cannot be recovered by disk utilities. You should only do this if you have a backup or you are sure you will never need the data again.

 

For machines which boot only Mac OS 9 or less, use Drive Setup, Apple HD SC Setup, or Internal HD Format, and select the option to zero out and/or low level format the disk. These programs are usually in the Utilities Folder on the install CDs for the various versions of the Mac OS. Apple Tech Note 21103 has more information.

 

A Shareware Option — ShredIt is cross-platform: it is an ideal choice for the multi-platform office. There is a ShredIt version for Mac OS X, Mac OS 9, Mac OS 8, Mac OS 7, Windows 95, Windows 98, Windows NT, Windows 2000, Windows ME, and Windows XP. You can wipe a file or erase a hard drive with this easy-to-use File Shredder — computer privacy software that shreds data so it can’t be recovered. It’s available on a CD-ROM for $34.95 or $25.95 for the download. Users who need to dispose of confidential data on an ongoing basis appreciate how easy ShredIt is to use. Just drag the file on to the ShredIt icon and ShredIt File Shredder will wipe the file data so it can’t be recovered. If your not sure you need a shredding tool check out “Do you need a File Shredder? Take the ShredIt Data Shredder Test. It takes less than 2 minutes, to find out.”

 

I’ve tested the software in trial mode, and it appears to be a fine product, but full testing will wait my having more time. Of importance to me is that ShredIt shreds everything. It will erase a file, folders, disk free space, files you’ve already deleted, whole hard drives, external hard drives, thumb ‘flash’ drives and even a floppy or a Zip disk. Now I do the later medium with an old tape degausser, left over from my reel-to-reel days.

 

Remember: Throwing data in the computer trash does not remove the file contents from the hard drive; the data can be recovered by someone else. Users who want to erase a hard drive before disposing of a an old computer can be confident that using ShredIt Hard Drive Cleaner will erase the hard drive so the data cannot be recovered by the next owner.

 

In Part from Apple Barrel, Ridgecrest, CA

Harry Babad, macCompanion

From Paul Taylor’s Hints and Tips Newsletter – October 2007

PS

 

I can’t let a thought flyaway undocumented, so back to restore simply trashed data. Check your favorite software supplier or do a quick Google or MacUser search to identify many of software tools for trashed file recovery will allow anyone to restore that data. Do read the review carefully because a bad tool can do more damage that you should bargain for. Focus on both how well they work and their ease of use. Check blogs to see what havoc they a product might have caused — remember the software vendor is not liable to Caveat emptor.

 

Why - Who Needs It?

 

Oh, you accidentally trashed that term paper or the draft of your new book you were working against the clock to complete. Your backups our out of date, so where do you turn? Hard disk recovery tools of course. The same tool gave the capability to bulletproof your drive that even a supper computer will have trouble getting at your data. Examples of available product include Data Rescue II and low-rated Disk Doctors Mac Data Recovery 1.0. There’s one I’d not heard of before [Macintosh Data Recovery which seem to be associated with a data recovery service. Despite the seemingly similar titles, they seem to be different products.

 

PPS

 

Next month: eMail Etiquette — based on what fills my inbox, no not spam, you have not heard it all yet!