Unless you’ve been locked in a room somewhere for the past few months, you know that Friday is the official release date for Mac OS X 10.5, a.k.a., Leopard. Upgrading to a major new version of a computer’s operating system is a major undertaking, no matter how easy the process is supposed to be; as you’ll see in our upgrade guide, to be published on Friday, there are a number of choices to be made and precautions to be taken. But the most important thing to do beforehand is back up . There’s no upgrade-related problem so big that it can’t be fixed by erasing your drive and restoring it to its pre-upgrade state. (On the other hand, there are few computer-related disasters worse than not having a backup and then losing data thanks to a problem with an upgrade.)
With that in mind, it seems an opportune time to cover a recent—and major—update to one of the oldest Mac Gems, Mike Bombich’s Carbon Copy Cloner. First reviewed back in July 2002, Carbon Copy Cloner was, at the time, the only utility that could reliably duplicate a Mac OS X volume, making a bootable clone. Many people, including myself, considered it to be an invaluable tool for any Mac OS X user.
In the years that followed, Carbon Copy Cloner (CCC for short) received several useful updates, but other utilities eventually came along that offered considerably more functionality and better interfaces—most notably SuperDuper ( ). But with Carbon Copy Cloner 3.0.1 ( ; payment requested), the gap has narrowed considerably.
For those unfamiliar with the concept of a clone , it’s an exact copy of a volume, preserving all invisible files, permissions, metadata, and other information that some traditional backup applications—as well as the Finder—don’t actually copy. In fact, an accurate clone is the only way to create a bootable backup of a Mac OS X disk—a backup that lets you get back up and running in a matter of minutes, as opposed to the hours it might take you to reinstall Mac OS X on a drive and then restore your files. (Note that you need to clone to a drive that’s actually capable of booting a Mac; not all drives are.)
But a clone is also useful when upgrading to a major new version of Mac OS X: You can clone your Mac’s hard drive to another drive; then use the OS X Installer to perform an Erase And Install of the new OS on your Mac; and then connect the clone to your Mac and use Setup Assistant to automatically migrate your user accounts, settings, and data from the backup to the new OS X installation.
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Carbon Copy Cloner, like SuperDuper, lets you easily create just such a clone. You just choose a source disk (the original volume) and a target disk (the backup volume); choose Copy Everything From Source To Target from the Cloning Options pop-up; and, optionally, enable the option to Erase The Target Volume. Click on Clone and an exact copy of the source disk will be made using the target disk. (In a not-so-subtle nod to SuperDuper, you’ll see a clear description of the backup operation in the What Is Going To Happen box. To be fair, SuperDuper uses the text “What’s Going To Happen,” so there is—or there’s , depending on your inclination—at least one difference in the wording.) The process isn’t fast, but it’s thorough.
One unique option here is the ability to make a block-level clone. This method makes a clone that’s not only file-by-file identical, but also block-by-block identical. There are few situations in which a typical Mac user will need the latter, but if you do, CCC will oblige, provided CCC is able to unmount both the source and the target—which means you can’t be booted from either—and you choose the option to erase the target volume. If not, the option won’t even be available.
(Like SuperDuper, you can also clone to a disk image. This can be convenient, for example, for backing up multiple Macs to a single, large hard drive.)
An improvement to CCC in version 3 is in how you choose to perform an incremental clone—in other words, to update an existing clone backup to reflect recent changes to your Mac’s hard drive, without having to copy the entire drive over again. However, it’s still not the most obvious feature. From the Cloning Options pop-up, choose Copy Selected Items; this displays the contents of the source disk. If you perform a backup now , only files that have changed on the source disk will be copied to the target disk; other files on the target—including any that don’t exist on the source (for example, because they’ve been deleted from the source) will remain untouched.
This approach effectively gives you both an incrementally-archived clone of your hard drive—one that contains older and newer versions of each file—as well as an archive of files deleted from the source. One caveat here is that you need to watch your target (backup) disk over time to make sure it doesn’t fill up. Adding the Delete Items That Don’t Exist On The Source option will do just that—your clone will always be exactly the same as your hard drive; items deleted from the source will also be deleted from the backup. (The Archive Modified And Deleted Items option keeps deleted-from-source items on the backup drive, although it moves them to a folder, named after the date the items were deleted, at the root level of the backup drive.)
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One of the most appealing features of Carbon Copy Cloner 3—especially for advanced users—is the ability to clone only particular files. After choosing the Copy Selected Items option, which reveals the contents of the source drive, you can uncheck any files or folders you don’t want included in your backup. This option can be handy for backing up, say, just the /Applications, /Library, and /User folders. Similarly, the Action (gear-icon) pop-up menu provides options for creating and applying filters that restrict what will be copied; for example, you can force Carbon Copy Cloner to not copy JPEG images or music files.
Also useful is the Advanced Options window, accessible via the Carbon Copy Cloner menu, which lets you copy the selected files to a particular folder on the target volume—for example, to a folder on a network volume or on another Mac.
Keep in mind that by choosing a selection of files or copying to a folder, you’ll end up with in a clone that’s incomplete and possibly non-bootable. For that reason, I don’t recommend this approach for your only backup or for use by those who wouldn’t understand how to use such a partial backup to restore their Macs. I also wish CCC would display the total size of the chosen files, so you could tell if your target volume will be able to accommodate them. Finally, in my testing copying a subset of files to a folder on another drive, several invisible folders not displayed in the Carbon Copy Cloner list— dev and Volumes —were copied, empty, to the target folder.
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Scheduling is another area that’s been improved in CCC3, although, again, how to schedule a backup operation isn’t entirely obvious. Once you’ve set up your desired copy options, click on Save Task. A Backup Task Scheduler window will open, where you can choose to perform this particular cloning task on an hourly, daily, weekly, or monthly basis (with options to choose every x number of hours, days, weeks, or months). Or you can set the backup to occur whenever the target volume is reconnected—an especially useful option for backing up to an external drive. Oddly (at least in my opinion), if you want to back up on particular days—for example, every weekday—you choose On A Weekly Basis, which lets you then choose the days of the week.
One usage tip: Browsing the CCC forums, I found a number of examples of minor issues with CCC 3, experienced by users of previous versions, that were fixed by deleting the files com.bombich.ccc.plist and com.bombich.ccc_helper.plist from ~/Library/Preferences. (The latter file may not exist for everyone.) So if you used an older version of CCC, and you have problems with version 3, try quitting CCC, deleting those files, and then relaunching the program.
So how does the latest Carbon Copy Cloner, which is “donationware”—remember to pay for it if you use it—compare to the Eddy-Award-winning SuperDuper ($28)? As I mentioned above, CCC makes it easier to clone a particular folder other than the Users directory. It can also securely copy selected data to another Mac over a network or the Internet. And CCC claims to work better when backing up data to an iPod; according to the documentation, CCC waits to give iTunes a chance to sync with the iPod before backing up. (I didn’t test this particular feature.)
On the other hand, I think SuperDuper’s interface is still clearer and easier to use; as just one example, it’s easier to figure out how to do an incrementally-updated clone (in my experience, the most common type of backup using these utilities). SuperDuper also provides several useful cloning options (explained in our review of version 1.5.5 ), including the unique Safety Clone; a good number of additional features; and, based on my own experience and feedback from readers, great tech support. (Most CCC support is apparently handled through the Bombich Software forums.)
Whichever utility’s features you find more appealing, it’s great to see some competition in this specialized area of Mac software.
Carbon Copy Cloner 3.0.1 requires Mac OS X 10.4 or later; it is compatible with Leopard (Mac OS X 10.5).