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I have an old iBook (Model A1007) that I would like to donate, but first I need to delete all of the last user's data so that it is not recoverable. With Windows machines, I usually do this by running a live Linux USB or CD and then using the "shred" tool to overwrite the hard drive some number of times with random data.

Unfortunately, I have been having trouble running live Linux on this Mac, as per this post: booting an iBook from a live linux usb drive. Booting from a CD instead hasn't seemed to have given me more useful results.

It seems that if I were to purchase the Mac OS 10.4 installer disk, it might be able to do what I need, though since I am doing this just to get rid of the computer, it seems like a bit of an excessive investment for what I am trying to do.

My problem is similar to this one: Securely wipe all user data from iBook G4 / OSX 10.4?. That user had three proposed solutions

  1. Connect the computer to another Mac. I'd rather not, as I don't have another Mac.

  2. Clone the entire computer to an external disk and then run it off that. This seems like it is going to likely be a big project involving lots of debugging (and somehow finding a blank external hard drive, which I would prefer to avoid as well).

So my questions are:

  1. Is there some free way to either run Linux on this old iBook and use that to wipe the data?

  2. If not, is there some other free way to securely delete the data from the iBook?

  3. If neither 1 nor 2, is there a way that will minimize hassle and expense to clean this computer so that I can get rid of it?

I'm not above breaking this thing open and physically destroying the hard drive, if I must. I'd just rather use software means if its possible (and not too expensive).

Allan
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ohnoplus
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3 Answers3

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You can use the Disk Utility program supplied by Apple - and you can tell it how many overwrites you wish it to do, the last time I read that info it said one pass was not very reliable, 7 should be fine and 35 was overkill - bear in mind how long it takes to do one complete pass....

A similar question is here : Selling a Macbook Pro - removing personal information from it

Edit: You need to boot from a different media as it cannot work on itself so, either the original install disc or a newer install disk for a later version - as older ones don’t usually work forwards... Other bootable media may also work - but that I have not tried...

Solar Mike
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  • Just to confirm: this approach would require a copy of the mac os installer DVD. Right? – ohnoplus Feb 11 '18 at 04:49
  • You need to boot from a different media as it cannot work on itself so, either the original install disc or a newer install disk for a later version - as older ones don’t usually work forwards... – Solar Mike Feb 11 '18 at 06:27
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You need to boot the iBook from supported boot media (like a compatible or retail PPC Mac OS X installer CD or DVD) to do this. Another way is using PPC compatible Linux, but an older version for the G4 CPU. Ubuntu 9.x is a good candidate, as is YellowDog Linux. Gentoo is known to have a working ISO image, ready to burn, but that probably is harder to track down. Booting from USB was not really supported, some OpenFirmware versions did make it available, but it was flaky at best. Machines that were the most reliable regarding USB boot were the G5 Towers and G5 iMacs.

Keep in mind that before you do all this you may want to ensure you have the latest firmware updates installed. While there haven't been any updates for a decade, it is still possible that a previous owner has not installed them all, and you can't do it without a Mac OS installation.

For reference, a link to a known working Linux CD ISO image (I have a PPC G4 1.2Ghz white iBook here as well, works with that CD): http://old-releases.ubuntu.com/releases/ports/releases/9.04/release/ubuntu-9.04-alternate-powerpc.iso

This is the 'alternate' image, which should allow you to boot a bit faster on low-memory machines and has a few extra tools to allow you to wipe the disk (I'd suggest just writing zeroes to the whole thing, or if you are paranoid use /dev/urandom and write that to the /dev/hda or /dev/sda). When it boots, you can just ignore the installer and move directly to 'recovery shell' to get going.

John Keates
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  • This seems super promising. ubuntu-9-04-alternate-powerpc does indeed run and I can get a rescue shell up. The screen before the rescue shell tells me that 'The hard disk file systems are mounted on "/target".' When I run the shell target doesn't appear when I ls / and cd \target tells me "can't cd to \target. I also can't find /dev/hda or /dev/sda. Is there some reason that the shell wouldn't be recognizing the hard drive? – ohnoplus Feb 11 '18 at 18:46
  • That message was probably just a static suggestion added to the installer. With ext-formatted systems it would probably mount it on /target as it is designed to rescue an existing linux install. Regarding the disk, you can try dmesg for any messages regarding found hardware. In some cases it might be under a different label due to the APM style disk on an Apple-specific controller. You can list all devices with a d in it using ls /dev/d – John Keates Feb 11 '18 at 21:26
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Use srm (secure removal of files/directories) to securely delete the User folder with your personal data.

srm has been in OS X since 2004 so it's included with Tiger. This will allow you to securely delete your files without affecting the rest of the OS. This has the added advantage of whomever you're donating to doesn't have to go through the trouble of finding install media to get the machine working again.

  1. Boot your iBook
  2. Create a new user with Admin priviliges
  3. Log out and log back in as the user you just created
  4. Open Terminal
  5. Navigate to the the /Users folder
  6. Issue the command srm -rf [Username]
  7. Close Terminal
  8. Go into System Preferences >> Users & Groups
  9. Delete the old user

That's it... Your personal data is gone and you don't have to go though any convoluted steps to boot Linux.

As for srm and the level of security, you can add the following flags:

  • -s = simple; overwrite with a single pass of random data
  • -m = medium; overwrite with 7 DoD compliant passes
  • -z = zero; after overwriting, zero the blocks used by the file

You can get more info on srm from the man page (man srm)

Allan
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  • This has the downside of not erasing the free space and still leaving the machine with all non-user data like logs, licenses, software and an operating system that is no longer secure, or usable online. – John Keates Feb 11 '18 at 01:35
  • @JohnKeates - diskutil can erase free space and the Admin user can uninstall Apps and manually delete logs using the above method, but that was out of the scope of the question which was to *remove user data* – Allan Feb 11 '18 at 01:39
  • The scope in the question was somewhat larger considering the mentioned practice of applying shred a number of times. Also, sanitizing a system for sale should really be done completely, not just ‘a few spots where most user data might be’. With the lack of Recovery OS and unavailable install media, I’d go as far as suggesting cmd-alt-o-f and wiping the disk from OpenFirmware. It’s just that dumping a bunch of Forth here is incompatible with this site ;-) – John Keates Feb 11 '18 at 01:47
  • @JohnKeates- Why to all of that? What is it that makes you believe OS X saved clear text user data in places other than the User folder? What makes you believe that drives other than MFM and RLL require this level of security wipe? What you described is completely unnecessary. This is a good resource to reference: http://www.destructdata.com/dod-standard – Allan Feb 11 '18 at 11:40
  • It’s all based on ohnoplus’s question – John Keates Feb 11 '18 at 11:51
  • @JohnKeates - and my answer is based on what's correct. Just because the user wants to boot Linux to shred a device, doesn't make it the correct course of action. – Allan Feb 11 '18 at 11:58
  • Apparently my language was imprecise. I am happy to delete just user data, but deleting everything is slightly preferable in this case. I appreciate both answers. – ohnoplus Feb 11 '18 at 18:48