Working Mac

Backing up the data on your Mac is like flossing your teeth: the rewards make the tedium worthwhile. Until OS X, particularly version 10.3 (Panther), backing up your data was fairly routine. But Panther has complicated matters, raising new questions about what to back up, how to handle permissions, and how backups interact with FileVault-protected Home folders.

Read on to learn which folders in OS X are worth backing up, how to avoid permissions snafus that prevent file restoration, and how to keep FileVault from overwhelming your backup media.

Choose Your Weapon

There are two ways to prevent losing your data: backup programs and synchronization programs. The type of program you choose determines which OS X quirks affect you. See "Freedom of Choice” for a list of current programs of both types.

True backup programs, such as Dantz Development's Retrospect 6.0 (   ; June 2004), make a copy of each revision of a document, so you can restore not only the latest version of your FileMaker customer database, but also last Tuesday's version, from before someone deleted all the 2003 records. Backup programs usually store backed-up files in some sort of proprietary format, so only the backup program can restore them, and they often work with backup devices, such as tape drives, that don't typically mount on the desktop.

Synchronization programs, such as Econ Technologies' ChronoSync, copy only the current version of a document. They commonly write only to Finder-mountable devices (external hard drives, network volumes, CDs or DVDs, and so on). Synchronization programs are ideal for making and maintaining an exact duplicate of your hard drive, which is great if your Mac dies -- you can boot from the duplicate. But synchronization programs are less useful if you discover too late -- after a duplicate has been made -- that you need a previous version of a file or a file that you deleted before the latest synchronization.

Choose What to Back Up

Whether you use a synchronization app or a full-fledged backup program, you'll face the question of what to back up. Backing up everything makes for the easiest restores, but what if you want to save time and media?

If you follow Apple's guidance and store files in your Home folder's special folders (Desktop, Documents, Library, Movies, Music, Pictures, Public, and Sites), the answer is easy: back up your entire Home folder. However, that's still a lot of data. To pare it down, target files you can't replace without cost (music purchased from the iTunes Music Store, for example) and leave out files you can replace (music ripped from your own CDs).

Also consider backing up your Applications folder and the top-level Library folder. You could reinstall applications from original discs or new downloads, but that could take days. And although most preferences are stored in the Library folder in your Home folder, the top-level Library folder can contain important configuration files.

If you're still using OS 9 occasionally, or if you haven't entirely switched to using OS X's default folders, your top-level Documents folder and Desktop (Mac OS 9) folder may have valuable data and should be part of your backup. Your OS 9 Applications folder -- labeled Applications (Mac OS 9) -- and System Folder are also worth protecting, at least until you've weaned yourself from OS 9 and the Classic environment.

Mother, May I?

To avoid downtime after a disaster, use a synchronization program to duplicate your entire hard drive to an external drive. You can restore files from the external drive and, if necessary, boot from it. But regardless of the program you use, if you disregard one little option, your duplicate won't boot OS X -- and if you restore from it, the restored drive won't boot, either.

This is because every file and folder in OS X is associated with a particular user and has specific permissions that control how other users can view or edit the contents (not at all, read only, or read and write). Although these permissions may seem irrelevant to backing up data, they can be essential when restoring it, particularly with system files and some applications.

Permissions issues crop up only when you use a synchronization program to copy files to another volume such as a hard drive or a network server. Backup programs that store files in a proprietary container format (for example, a Retrospect file-based backup set) don't suffer from these permissions troubles because they can track the permissions inside the backup container.

External Hard Drives To preserve ownership and permissions when copying files to an external hard drive, open the Get Info window for that drive and deselect the Ignore Ownership On This Volume option. That's necessary to back up and restore system files properly when using a synchronization program (you can't copy them correctly via the Finder). Ignoring ownership isn't as important with data files and applications; you can restore them by copying them in the Finder, as long as you're logged in to an account that can read those files.

Network Volumes Network-mounted volumes are another story, since files copied to a server change ownership to match the account you use to log in to the server. So if you're logged in to your Mac as Larry, and you connect to an AppleShare server account called Curly, any files you copy to the server change ownership to Curly. And if another user, Moe, copies the files from the Curly account on the server, those files will change ownership again, to Moe. Nyuk, nyuk, nyuk.

For most documents and applications, this behavior is fine, since it makes sense that ownership matches the account copying the file. But some applications and many system files require specific ownership and permissions, so copying them to or from a network volume renders them inoperable.

Don't get burned by this behavior. When backing up only the documents you create, use a hard drive or a network volume and don't worry about permissions. But if you use a synchronization program to back up system files (as you would with a complete duplicate of your hard drive) or certain applications, stick to an external hard drive with the Ignore Ownership On This Volume option deselected.

Back Up FileVault

Panther throws another wrench into the works, with its FileVault security feature. FileVault protects all the data in a Home folder by copying the contents to an encrypted disk image, which is a single file that FileVault automatically mounts so it looks and works exactly like a Home folder. FileVault presents several problems for true backup programs; synchronization programs are less affected. (There are other drawbacks to FileVault as well. We don't recommend it, but if you already use it, follow these tips.)

To avoid wasting a lot of space on your backup media, a true backup program (which stores multiple versions of changed files) must have an option for ignoring the FileVault disk image. Otherwise, actions as minor as receiving a single e-mail message or editing a file would cause your entire multigigabyte FileVault disk image to be added to the backup set on every backup.

When you share your Mac with other users and want to back up only individual changed files within each FileVault-protected account, use Fast User Switching to make sure that each user is logged in before his or her account backup. This is true of all backup programs and some synchronization apps.

To Go Forward, You Must Back Up

Backing up data should be boring. Dramatic tension is great in the movies, but when your hard drive heads for the Clean Room in the Sky, you want to know that you've backed up the right files and that you can restore them to their original state. OS X may have introduced some new vagaries into the backup equation, but if you follow this advice, you can once again know that you're doing all you can to protect your data.

Microsoft versus Mellel

Microsoft Word undoubtedly dominates the word processing market, but there are alternatives. One little-known option is Mellel 1.7.5 ($29; www.redlers.com), from RedleX. Mellel is noteworthy for features such as citation management and foreign-language support, including the ability to display Unicode and right-to-left languages. -- terri stone

Researchers, Take Note

If your job requires research of a more scholarly nature than Google can handle, check out Thomson ISI ResearchSoft's EndNote 7 ($240; with manual, $300; www.endnote.com). With EndNote's databases, you can manage bibliographies and references. You can also search your own databases and many online resources.

Do you know undergraduate students struggling with research? Tell them about WriteNote (www.writenote.com), also from Thomson ISI ResearchSoft. WriteNote users can access online library resources, collect references, and format footnotes and bibliographies. WriteNote runs in a Web browser and is a subscription-based service (for K–12 schools, $750 per year; for colleges, price varies; free 30-day trial). -- terri stone

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