Time Machine

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6.4. Time Machine As the old saying goes, there are two kinds of people: those who have a regular backup system—and those who will.

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  1. 6.4. Time Machine As the old saying goes, there are two kinds of people: those who have a regular backup system—and those who will. You'll get that grisly joke immediately if you've ever known the pain that comes with deleting the wrong folder by accident, or making changes that you regret, or worst of all, having your hard drive die. All those photos, all that music you've bought online, all your email—gone. Yet the odds are overwhelming that at this moment, you do not have a complete, current, automated backup of your Mac. Despite about a thousand warnings, articles, and cautionary tales a year, guess how many do? About four percent. Everybody else is flying without a net. If you don't have much to back up—you don't have much in the way of photos, music, or movies—you can get by with burning copies of stuff onto blank CDs or DVDs (Chapter 11) or using the .Mac Backup program described at the end of this chapter. But those methods leave most of your Mac unprotected: all your programs and settings, not to mention Mac OS X itself. What you really want, of course, is a backup that's rock-solid, complete, and automatic. You don't want to have to remember to do a backup, to insert a tape, to find a cartridge. You just want to know that you're safe. That's the idea behind Time Machine, a marquee feature of Leopard. It's a silent, set it- and-forget-it piece of peace of mind. You sleep easy, knowing there's a safety copy of your entire system: your system files, programs, settings, music, pictures, videos, document files—everything. Yes, Time Machine has a fabulous, gorgeous, sci-fi, space-themed recovery mode, where it looks like you're flying back in time to retrieve files, folders, or disks from the past. With luck, you'll never need it. But if your luck runs out, you'll be so happy you set Time Machine up. 6.4.1. Setting up Time Machine Here's the bad news: Time Machine requires a second hard drive. That's the only way to create a completely safe, automatic backup of your entire main hard drive. That second hard drive can take any of these forms: • An external USB or FireWire hard drive. • Another internal hard drive.
  2. • A partition of any one of those drives. The hard drive of another Leopard Mac on the network. You must first mount its drive on your screen (Chapter 13). Tip: It's perfectly OK to back up several Macs onto the same external hard drive, as long as it's got enough room. You can also back up onto a hard drive that has other stuff on it, although of course that means you'll have less room for Time Machine backups. In all cases, the backup disk must be bigger than the drive you're backing up (preferably much bigger). Here's what you can't use as the backup disk: • An iPod. • The iDisk. • Your startup drive. • CDs, DVDs, flash drives, or any other kind of removable disk. Note: If Time Machine doesn't recognize the drive you've given it, the drive might not be a standard Mac-formatted hard drive. That's a gotcha that befalls many a Mac fan who buys a new hard drive for backup purposes; many new drives come in Windows format, which Time Machine doesn't recognize.To make a new, empty drive like this ready for Time Machine, open Disk Utility (Section 10.30.9). Click the drive's name, click the Erase tab, choose Mac OS Extended (Journaled) from the Volume Format pop-up menu, and then click Erase. Sure, it sounds like an Apple plot to sell more hard drives. But you'd be surprised at how cheap hard drives are. At this writing, you can buy a 300-gigabyte internal hard drive for under $90, for goodness' sake, or an external 500-gig drive for $125—and hard drive prices-per-gigabyte only go down. The first time the Mac sees your second hard drive, it invites you to use it as Time Machine's backup drive (Figure 6-5, top). That could be the moment you connect an external USB or FireWire drive, or the first time you turn on the Mac after installing an internal drive. If you click Use as Backup Disk, you're taken immediately to the Time Machine pane of System Preferences (Figure 6-6, bottom). It shows that Time Machine is now on, your
  3. backup disk has been selected, and the copying process has begun. The Mac copies everything on your hard drive, including Mac OS X itself, all your programs, and everyone's Home folders. Note: Time Machine doesn't use any compression or encoding; it's copying your files exactly as they sit on your hard drive, for maximum safety and recoverability. On the other hand, it does save some space on the backup drive, because it doesn't bother copying cache files, temporary files, and other files you'll never need to restore. Your total involvement has been one click. And that, ladies and gentlemen, is the easiest setup for a backup program in history. Now go away and let the Mac do its thing. The first backup can take a very long time— hours—as the Mac duplicates your entire internal hard drive onto the second drive. The Mac may feel drugged during this time. Figure 6-5. Top: The Mac has just encountered a second hard drive. Time Machine still works if there's other stuff on the drive, but life is simpler if you don't use that drive for anything but Time Machine. The more space Time Machine has to work with, the farther back in time you'll be able to go to recover deleted or mangled files. Bottom: The backup has begun. You know that because you see both a progress message and the symbol that appears next to the backup drive's name in your Sidebar. 6.4.2. How the Backups Work From now on, Time Machine quietly and automatically checks your Mac once per hour. If any file, folder, or setting changes, it gets backed up at the end of the hour. These follow-up backups, of course, take very little time, since Time Machine backs up only what's changed. So, should disaster strike, the only files you can lose are those that you've changed within the last 59 minutes.
  4. Tip: And even then, you can force more frequent backups if you want to. Any time you want Time Machine to update its backup before the hour's up, Control-click (or right- click) Time Machine's icon on the Dock. From the shortcut menu, choose Back Up Now.You can pause the backup the same way—if you need to use the backup drive for another quick task, for example. Control-click the Dock icon and then choose Stop Backing Up. (Don't forget to turn the backing-up on again when you're finished.) By the end of the day, you'll have 24 hourly backups on that second disk, all taking up space. So at day's end, Time Machine replaces that huge stash with a single daily backup. You can no longer rewind your system to 3:00 p.m. last Monday, but you can rewind to the way it was at the end of that day. Similarly, after a week, the dailies are replaced by an end-of-week backup; after a month, the weeklies are replaced by a single end-of-the-month backup. Now you can't rewind to October 24, but you can rewind to November 1. (Apple assumes that it won't take you a whole month to notice that your hard drive has crashed.) Tip: You can see these backups, if you want. Open your backup drive, open the Backups.backupdb folder, and open the folder named for your computer. Inside, you'll find a huge list of backup folders, bearing names like 2007-12-22-155831. That's the backup from December 22, 2007 at 15:58 (that is, 3:58 p.m.) and 31 seconds. The point is that Time Machine doesn't just keep one copy of your stuff. It keeps multiple backups. It remembers how things were in every folder—not just yesterday, but last week, last month, and so on. It keeps on making new snapshots of your hard drive until the backup drive is full. At that point, the oldest ones get deleted to make room for new ones. FREQUENTLY ASKED QUESTION The End of Time What happens when my backup drive gets full? Good question. The whole idea of Time Machine is that it preserves multiple backups, so that you can rewind a window or a drive not just to a backup, but to any date in the past. The bigger the hard drive, the farther back those monthly backups are
  5. preserved. Eventually, of course, your backup drive runs out of space. At that point, Time Machine notifies you and offers you a choice. You can keep using that drive; Time Machine will begin deleting the oldest backups to make room for newer ones. Or you can install a new Time Machine backup drive. New backups will go on that one; your older backups will still be available on the original drive. If you ever need to retrieve files or folders from the older disk, Control-click (right-click) the Time Machine icon in the Dock; from the shortcut menu, choose Browse Other Time Machine Disks. In the list of disks, choose the older one. Then click the Time Machine icon on the Dock to enter the Restore mode. Tip: Ordinarily, Time Machine alerts you when it has to start deleting old backups. If you'd rather have it just do it without bothering you, open System Preferences; click Time Machine; click Options; and finally turn off "Warn when old backups are deleted." By the way, if a backup is interrupted—if you shut down the Mac, put it to sleep, or take your laptop on the road—no big deal. Time Machine resumes automatically the next time you're home and connected. 6.4.3. Changing Time Machine Settings Time Machine has three faces in Leopard. There's the application itself, which sits in your Applications folder; click it to enter Restore mode. There's its Dock icon; its shortcut menu has a few commands (like Back Up Now) that aren't available anywhere else. And then there's its System Preferences pane, where you adjust its settings (Figure 6-6). To see it, choose System Preferences, and then click Time Machine. Or choose Time Machine Preferences from Time Machine's Dock icon.
  6. Tip: If your information is especially important, or if you're especially paranoid, you can rotate among more than one backup hard drive. Keep one offsite so you won't be hosed in case of fire, flood, or burglary. Figure 6-6. Use the big On/Off switch to shut off all Time Machine activity, although it would be hard to imagine why you'd want to risk it. You can click Choose Backup Disk to choose a different hard drive to represent the mirror of your main drive (after the first one is full, for example). 6.4.4. Recovering Lost or Changed Files All right, you've got Time Machine on the job. You sleep easy at night, confident that your life's in order—and your stuff 's backed up. Then, one day, it happens: Your hard drive crashes. Or you can't find a file or folder you know you had. Or you save a document and then wish you could go back to an earlier draft. Some kind of disaster—sunspots, clueless spouse, overtired self—has befallen your files. This is Time Machine's big moment. Start by pinpointing what you're looking for, in one of these two ways: • Open the disk or folder window where the missing or changed item was POWER USERS' CLINIC Declaring Stuff Off-Limits to Time Machine The whole point of Time Machine, of course, is to have a backup of your entire hard drive. That's how most people use it. It's conceivable, though, that you might want to exclude some files or folders from the Time Machine treatment. There are two reasons. First, you might not want certain, ahem, private materials to be part of your
  7. incriminating data trail. Second, you might want to save space on the backup drive, either because it's not as big as your main drive or because you'd rather dedicate its space to more backups of the essential stuff. For example, you might decide not to back up your collection of downloaded TV shows, since video files are enormous. Or maybe you use an online photo-sharing Web site as a backup for all your photos, so you don't think it's necessary to include those in the Time Machine backup. To eliminate certain icons from the backup, open the Time Machine panel of System Preferences. Click Options. In the resulting list, click the + button; navigate your hard drive, and then select the files or folders you don't want backed up. Or just find their actual icons in the Finder and drag them into the list here. (Use the – button to remove items from the list, thereby excluding them from the excluded list.) If you're strapped for disk space, one logical candidate to exclude is the System folder on your main hard drive—that is, Mac OS X itself. After all, if you lose your hard drive, you already have a copy of Mac OS X: the original installation DVD. (Of course, it doesn't have all the Apple updates that may have come out since the original version.) When you add the System folder to the exclusion list, Time Machine makes another space-saving offer: "Would you like to also exclude other files installed with Mac OS X, such as system applications and UNIX tools?" Agreeing (by clicking Exclude All System Files) saves you another several gigabytes of backup space. • • Type what you're looking for into the Search box at the top of any Finder window. Click the location button that makes the most sense: "This Mac" or the name of the window you're in.
  8. In the case of deleted files or folders, the search will probably come up empty; that's totally OK. Now click the Time Machine icon on the Dock (or in the Applications folder). Don't look away; you'll miss the show. Your Leopard desktop slides down the screen like a curtain that's been dropped from above. And it reveals…outer space. This is it, the ultimate Apple eye candy: an animated starry universe, with bits of stardust and meteors occasionally flying outward from the massive nebula at the center. Front and center is your Finder window—or, rather, dozens of it, stretching back in time (Figure 6-7). Each is a snapshot of that window at the time of a Time Machine backup. You have four ways to peruse your backup universe: • Click individual windows to see what's in them. • Drag your cursor through the timeline at the right side. it's like a master dial that flies through the windows into the past. • Click one of the two big, flat, perspective arrows. The one pointing into the past means "Jump directly to the most recent window version that's different from the way it is right now." In other words, it's often a waste of time to go flipping through the windows one at a time, because your missing or changed file might have been missing or changed for the last 25 backups (or whatever). What you want to know is the last time the contents of this window changed. And that's what the big flat arrows do. They jump from one changed version of this window to another. (Or, if you began with a search, the arrow takes you to the most recent version backup with a matching result.) • Use the Search box in the corner of the window. You can search for whatever you're missing in the current backup. As you go, the very bottom of the screen identifies where you are in time—that is, which backup you're examining. In many ways, the recovery mode is just like the Finder. You can't actually open, edit, rename, or reorganize anything here. But you can use Quick Look(page58)to inspect the documents, to make sure you've got the right version. And you can use icon, list, or Cover Flow view, as well as column view, to sort through the files you're seeing.
  9. If you're trying to recover an older version of a file or folder, highlight it, and then click the flat arrow button that's pointing away from you; Time Machine skips back to the most recent version that's different from the current one. If you're trying to restore a deleted file or folder that you've now located, highlight it, and then click Restore (lower-right). The Leopard desktop rises again from the bottom of the screen, there's a moment of copying, and then presto: The lost file or folder is back in the window where it belonged. Figure 6-7. This is the big payoff for all your efforts. Top: The familiar desktop slides down, dropping away like a curtain. For the first time, you get to see what's been behind the desktop all this time. Turns out it's outer space. Bottom: Time Machine shows you dozens of copies of the Finder window, representing its condition at each backup, stretching back to the past. Note: Time Machine prides itself not just on recovering files and folders, but also on putting them back where they belonged.If you recover a different version of something that's still there, Mac OS X asks if you want to replace it with the recovered version.And if you're recovering a document whose original folder no longer exists, Time Machine automatically recreates the folder so that the recovered item feels at home. Recovering from iPhoto, Address Book, and Mail It turns out that the Finder isn't the only program that's hooked into Time Machine's magic. iPhoto '08, Address Book, and Mail work with Time Machine, too. Other software companies can also revise their own applications to work with it. In other words, if you want to recover certain photos, addresses, or email messages that have been deleted, you don't start in the Finder; you start in iPhoto, Address Book, or Mail. Then click the Time Machine icon on the Dock. Once again, you enter the starry recovery mode—but this time, you're facing a strange, disembodied, stripped-down copy of iPhoto, Address Book, or Mail (Figure 6-8).
  10. Tip: Alternatively, in iPhoto, you can also choose File Browse Backups to enter recovery mode. Figure 6-8. The Time Machine version of iPhoto is a weird, simplified, viewing-only version. You can't do much here besides browse your backups— but when you're in dire straits, that's enough. You're ready to find your missing data. Click the Jump Back arrow to open the most recent version of your photo library, address book file, or email stash that's different from what you've got now. (You can also use the timeline on the right if you remember the date when things went wrong.) Tip: If you're looking for something particular, specify that before you start clicking. For example, select the iPhoto event or album first, or type a name into the Address Book search box. At this point, you can select individual photos (or albums, or events), address book entries, or email messages to restore; just click the Restore button. Often, though, you'd rather reinstate the entire iPhoto library, Address Book file, or email collection from the backup. That's what the Restore All button is for. If you click it, the experience is slightly different. iPhoto asks if you're sure you want to replace your iPhoto library. Address Book may discover a lot of duplicate name and- address entries, and invite you to step through them, deciding which one "wins" (the old or the new). Note: When you finish restoring in Mail, you'll find the restored messages in the On My Mac Time Machine Recovered folder at the left side of the window. Recovering the entire hard drive
  11. Every hard drive will die at some point. You just hope it won't happen while you own the computer. But the great gods of technology have a mean-spirited sense of humor, and hard drives do die. But you, as a Time Machine aficionado, won't care. You'll just repair or replace the hard drive, and then do this: 1. Connect the Time Machine backup disk to the Mac. Insert the Leopard installation DVD. Double-click the Install Mac OS X icon. The Mac OS X installer opens up as though it's going to lead you through the process of putting Leopard on the new, empty hard drive. But don't fall for it. 2. At the Welcome screen, choose Utilities Restore System from Backup. The Restore Your System dialog box appears. 3. Click Continue. Now you're shown a list of Time Machine backup disks. You probably have only one. 4. Click your Time Machine backup disk. In the list of backups, click the most recent one. The installer goes about copying everything from the backup disk onto your new empty hard drive. When it's all over, you'll have a perfect working system, just the way it was before your series of unfortunate events. Tip: You can use these steps to rewind to a previous version of Mac OS X 10.5, too—for example, after you install an Apple software update (10.5.2, say) and discover that it "breaks" a favorite program.Beware, however: Restoring your earlier version also erases any files that you've created or changed since you've installed the update. Back them up manually before you proceed!Then follow the steps above; when you're asked to choose a backup to restore, choose the most recent one. When it's all over, copy the latest files (the ones that you manually backed up) back onto the hard drive. Recovering to another Mac
  12. Weirdly enough, you can also use Time Machine as a glorified data bucket that carries your world from one computer to another. You can bring over some or part of any Time Machine backup to a totally different Mac. On the new machine, connect your backup disk. In the Applications Utilities folder, open the program called Migration Assistant. On the first screen, click "From a Time Machine backup." The subsequent screens invite you to choose which backup, which Home folder, and which elements (applications, settings, files) you want to bring over. (You can use the Leopard installation DVD for this purpose, too, as described above.) 6.4.5. Frequently Asked Questions Time Machine is a very different kind of backup program, and a real departure for longtime Mac addicts. A few questions, therefore, are bound to come up—like these. • Can I back up more than one Mac onto the same disk? Yes. Each Mac's backup is stored in a separate folder on that disk. • Does the backup disk have to be dedicated to Time Machine? No. It can have other files and folders on it. Keep in mind, though, that the more space is available, the farther back your backup trail can go. UP TO SPEED .Mac Backup Time Machine is by far the most complete, effortless, automatic, safe way to keep your data life safe. There's an older method, though, one that's available only to members of .Mac, Apple's $100-a-year suite of Internet services. .Mac membership includes access to a program called Backup, which can give you another automatic backup system for a subset of your files—your most important files. The beauty of this method is that the backup is offsite, so (unlike Time Machine) it's safe even if fire, flood, or burglary destroys your backup drive. If you're interested in this oddball little program, consult the free downloadable PDF appendix to this chapter, called ".Mac Backup." It's available on this book's "Missing CD" page at www.missingmanuals.com.
  13. • Can I use more than one back up disk—like one at the office and on eat home? Yes. Just use the Time Machine panel of System Preferences (or the Time Machine Dock icon's shortcut menu) to select the new backup drive each time you switch. • Can I delete something for good, from all the back ups at once? Yes. Click the Time Machine icon on the Dock to enter the Restore (outer-space) mode. Find and select the file or folder you want to obliterate. From the menu, choose Delete From All Backups. (Sneaky, huh? That command is never in the menu except when you're in Time Machine restoring mode.) • Can Time Machine back up other hard drives besides the main internal one? Yes. Open System Preferences Time Machine. Click Options. Your secondary drives are listed here on the excluded-items list. If you want them backed up too, remove them from the list (click the drive name and then click the – button.) • Anything else you want to get off your chest? Yes. Time Machine has trouble with three kinds of files: First, File Vault (Section 12.9.2). If you've encrypted your Home folder using File Vault, Time Machine can back up only your Home folder only when you've logged out. And when things go wrong, it can recover only your entire Home folder (not individual files or folders). It scarcely seems worth the trouble. Second, Aperture. Turn off Time Machine backing-up while you're working in Aperture, Apple's professional photo-organizing program. Finally, remember that Time Machine backs up entire files at a time—not pieces of files. If you edit huge, multigigabyte files like video files, therefore, keep in mind that each giant file gets recopied to the backup drive every time you change it. That is, one 2-gig video file that you work on all day could wind up occupying 48 gigabytes on the backup drive by the end of the day. Consider adding these files to the exclusion list, as described above.
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