Hard drives die. And when they do, it’s a royal pain in the butt. To make it a little less painful, drive manufacturers have included a self diagnostic utility on modern hard drives. It’s called Self Monitoring, Analysis, and Reporting Technology or SMART. (My, aren’t we clever?) In this post, we’ll go over how to check the status of your hard drive using SMART on OS X.
SMART is kind of like a “Check Engine” light for your hard drive. It’s supposed to give you a heads up if the drive notices something odd. Ideally, that would give you a chance to replace the drive before it kicks up its little electronic heels and has little “X”s over it’s eyes.
Unlike your check engine light, there’s no blinking notification for a drive SMART failure on your dashboard. You have to go look for it. Fortunately, this is really simple in OS X. Just open up “Disk Utility” (in the “Applications”–>”Utilities” folder.)
I’ve clicked on my internal hard drive. In this case, you can see at the bottom that my hard drive SMART status is “Verified”. Compare this to my personal smart status, which is, “not very”. (Yeah, you probably saw that joke coming a mile away.)
If your hard drive is failing, you’ll see lots and lots of stuff in red. Apple really went out of their way to make sure you won’t miss the fact there’s a serious problem.
Unfortunately external drives, such as USB and Firewire disks, don’t support SMART, so you don’t get any head up if the start to fail.
I suggest that you simply open up Disk Utility once every week or so. You can quit it as soon as you’ve seen there’s no big red letters.
What do you do if you do see the red letters of impending doom? Do not pass go. Do not collect $200. Backup as much data as you can if at all possible. I’ve got instructions on full backup, full restore, and regular backup. (Don’t be surprised if you can’t make a backup at this point. Your drive may be too ill of health to work properly.) Then install a new hard drive as soon as possible.
Does checking your drive’s SMART status mean you’ll be able to avoid every hard drive failure? Certainly not. In my own practice, I’ve only seen one instance where SMART let me know before it was too late. Just like your “Check Engine” light, there’s lots of things that will make your car die without ever turning on that light. So make sure you back up regularly!
August 16th, 2007 at 5:20 pm
I have a related question. I have a Mac g5 running 10.4.7. Previously I had the g3 desktop and used Norton disc doctor and optimization software. With the new mac OS X is it necessary at any point to run a disc software program to optimize the drive and thereby making fragments contiguous for optimization?
If so what software would you recommend? Disk Warrior? Thanks
August 16th, 2007 at 5:40 pm
As of OS X 10.3, the operating system defragments itself on the fly. As long as you follow the golden rule of about 10% free disk space, it will handle all of this for you.
You should definitely NOT use Norton Utilites on an OS X volume. I’ve seen it do some damage that the disk was no longer bootable. It was something I was able to fix, but the person watching said what I did looked like a lot of magic.
I really don’t use any particular disk utilites other than the standard “Disk Utility” application Apple includes. The rest of the maintenance is handled automatically.
August 23rd, 2007 at 6:20 pm
Mr. Rhodes,
I happened to check your page to see if I received a response on my disk maintennance question and was pleased to see that I did.
I did read something some time ago regarding Norton Utilities doing nasty things to the Mac OS. I was not aware that the new OS did disk maintennance on it’s own so I appreciate you informing me. It likely saved me some money and possibly headaches I would not have been pleased with. Once again thank you. I will be watching your website from this point forward for useful info and tips.
September 25th, 2007 at 12:42 pm
I went into the Utilities folder to verify my disk. I was able to verify the permissions abut the Verify disk button was not dark and therefore I was unable to verify. What could the reason for this be?
Thanks in advance.
September 25th, 2007 at 12:55 pm
It might be a difference in versions of OS X. I know in some earlier versions, you couldn’t do either (verify or repair) to the disk you were running from. The solution is to boot from another OS X source and run Disk Utility. Where do you find another OS X installation that will run on your computer? Boot from your OS X installation CD. Hold down the “C” key while the machine starts. Instead of installing, pull down “Disk Utility” from the “Installer” menu. More info from Apple here: http://docs.info.apple.com/article.html?path=DiskUtility/10.5/en/duh1018.html