how to secure your mac (OS X Lion)

Security in OS X Lion is a big problem that not many people are aware of, and here’s why: your Lion computer contains the install/recovery disk on the internal drive. That means anyone with a basic knowledge of Mac and Lion can start up your mac and reset your passwords, thereby accessing your user accounts and all your personal data. The same trick can help kids easily get round restrictions applied through OS X’s ‘Parental Controls’ feature.

How is this possible, you may ask? First, a little history. Among the 250 changes vaunted about Lion over its predecessor, Snow Leopard, there is one that is widely known but whose implications are rarely pointed out: you download the OS rather than install it from a disc. In the past, if your OS went bad and needed to be recovered, or you forgot your admin passwords, the simplest answer was to insert your install disk. From that, you could restore the OS and reset your passwords. That made your Mac a little safer (though not entirely safe) so long as your disc was kept somewhere physically different from your computer.

With Lion having no install disc, Apple had to find an answer as to how to provide the recovery option. The solution was to install a Recovery partition on the same disk as the operating system itself. In the event that the OS goes bottoms up and needs to be recovered or re-installed, you just restart your computer holding down the ‘command’ and ‘r’ keys to access the Recovery partition.

So far so good, but likewise, just as with the old DVD install discs, you — or anyone else — can also reset the user account passwords from the Recovery partition. That means your passwords are effectively useless. Anyone who wants to hack your user account just has to restart your Mac holding down ‘command’ and ‘r’ and then use the built-in Password Utility to make new passwords for your accounts. Now I’m not going to tell you quite how to do it (you do need a little knowledge to get the user account names and know how to do the reset) but it is widely publicized elsewhere, and indeed even in Apple’s own online documentation (so if you really want to know, google is your friend or follow some of the links in this post…).

What’s the answer to this security nightmare? Here’s one thing that’s NOT the answer but which I have seen widely touted: setting a firmware password. If you’re not familiar with the concept of the firmware password, don’t worry. It is practically useless, since anyone can reset that simply by taking off the back of your computer, and then pulling out and then putting back in one of the memory chips.

Apple, of course, thought about this problem. Their own solution is to encourage you to use FileVault 2 (FV2) to encrypt all your data. Indeed, this is the BEST solution. Without your password, no one can access the disk on your computer no matter what they do (and that includes YOU if you forget it…). However, there are a couple of drawbacks to FV2. One is that it requires extra disk space, and if you have more than one partition on your hard drive, or a lot of data, and little space you may not be able to encrypt and decrypt your data. The other drawback is that FV2 places a little extra wear-and-tear on your hard disk (though that may be negligible given the security pay off).

Using FileVault 2 is really the only security option if you’re using Lion. However, if you don’t have the space for it, there is a ‘second-best’ strategy (see below why it’s only ‘second best’), and that is to remove the recovery disk and use a clone as your recovery option instead (WARNING: the Recovery disk is required for FileVault 2, so by removing it you will also remove the ability to use FV2).

There’s a couple of ways to remove the recovery partition on your internal disk, but this is probably the best:

1. Clone your current system to an external disk using Carbon Copy Cloner. This will clone your entire system exactly as it is now, but it will not copy the Recovery disk.

2. Still booted into your internal OS (the one on your machine), open Terminal.app and paste the following command:

defaults write com.apple.DiskUtility DUDebugMenuEnabled 1

Press ‘Return’.

3. Open Disk Utility.app (Applications/Utilities/Disk Utility.app). In the menu bar of Disk Utility, choose Debug > Show Every Partition.

4. In the left-hand pane of Disk Utility, you can now see the Recovery HD. Click on it. Then click on the Erase tab on the (larger) right-hand pane. Click the Erase button down there on the bottom right.

5. Quit Disk Utility.

Now you can use your bootable clone as your recovery disk if your OS becomes corrupt and no one can boot up your computer with ‘command-r’. If you keep the clone backed up on a regular incremental schedule (you can choose anything from once an hour, once a day, week, or month), you can simply restore a corrupted internal disk to exactly the same state as your last backup.

Why only ‘second best’?
As alluded to earlier, it is still possible for advanced users to start up your mac and reset the password without the Recovery partition (this was also true in Snow Leopard even without the install disc). In fact, what this procedure does is give your OS X Lion installation the same security level as an OS X Snow Leopard installation, which is not actually that great, but better than Lion with a Recovery disk! Also, if you are storing highly sensitive data, don’t neglect the fact that someone who has complete unfettered access to your hard drive could even remove the disk and recover the data using special software.

The short story is if you want to be absolutely certain that your data is secure, FileVault 2 is really your only option.



featured picture Security Workstation by digitalhadz

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need a manual for Lion?

Got a new Mac and feeling like you’re on a whole different planet? Providing user manuals with computers isn’t really very Apple somehow 😉 …after all, the OS is supposed to be so intuitive and easy to use we shouldn’t need one…

However, clearly more than a few have been having problems getting used to their new Lion installation as Apple are now prominently displaying two beginners help guides on the ASC support forum.

Have a look at Mac 101 if you’re new to computers in general or haven’t really used one for a while.

If you’re pretty computer savvy but have just switched over from a lifetime of Windows to your first Mac, then Switch 101 will clue you into both some of the major differences and how to accomplish familiar Windows tasks in your new Mac OS X environment.

To keep up to date, troubleshoot, or find answers to specific questions not covered in the above materials, be sure to visit http://www.apple.com/support/lion/. You can also find this page from the  menu at the top left of your screen. Click

 > About This Mac and then ‘More Info…’:

Over on the right of the next panel, click the ‘Support’ button:

You can access both the online Lion manual (indicated in blue), and also a pdf manual (indicated in purple) for your computer from here.

Enjoy exploring! 🙂

Struggling with the basics? Don’t be shy, let us know in the Comments below! 🙂

featured picture The Close Light by *qaz2008

how to unfreeze your iPad

iPads are so easy to use, why bother with the manual? 😉 The chances are though, that at some point you’re either going to find that an app freezes on your screen or your whole tablet becomes unresponsive. Don’t panic, the answer’s simple:

First, be sure that it’s connected to a power source. The most common reason for iPads not working is people don’t realise they’re out of battery! Otherwise try these:

If it’s just a particular App that’s frozen on your screen:

— Hold down the ‘sleep/wake’ button (top right, back edge) for about 5 seconds until the slider appears. Release the ‘sleep/wake’ button. Now hold down the ‘Home’ button (bottom front, centre) until you see your Home screen.

If your whole machine is unresponsive, then do a restart:

— Hold down the ‘sleep/wake’ button for about 5 seconds until the slider appears. Slide it to ‘Off’. Then hold it down again until the Apple logo appears showing that the iPad is restarting.

If that doesn’t work, do a hard reset:

— Hold down the ‘sleep/wake’ button AND the ‘Home’ button simultaneously for about 10 seconds or until the Apple logo appears.

*For more serious problems with your iPad, such as continual restarting or no home screen, have a look here.

featured picture: ice crystals by Typen