Backing Up Your System


If you use a computer, at some point, your system will crash, a disk will fail, or some other problem will happen (perhaps you will delete something you didn't mean to) and you will lose data you would rather not losemaybe not today or tomorrow, but it is the inevitable nightmare. Think of the information you have on your Mac at this very moment that would be difficultif not impossibleto reconstruct if your computer bombed and destroyed it. This data might be a report for work, a school project, your tax information, a complex spreadsheet, or even the great American novel on which you have been working. (For example, imagine that you have 2,000 photos in your iPhoto Library covering the last few years. Now imagine that the disk on which these images are stored dies. Losing all those pictures forever is not a pretty picture, is it?) Whatever the information, rest assured that some day, somewhere, somehow you will suddenly lose it. When that happens, you will want to be able to restore all the information on your Mac so you can quickly re-create your data. Backing up is the means by which you ensure that you can always preserve most of your work, no matter what happens to your Mac.

Backups: Insurance for Your Data

You need a good backup for more than just catastrophic failures of your hardware. I'll bet that you have accidentally deleted a file right before you needed it again. If you have a backup, you can quickly recover a document you accidentally delete. Or perhaps you edited a document and discovered that all your changes were actually worse than the original. You can use your backup to bring the file back to the way it was. If your Mac is ever stolen or destroyed, your backup will enable you to recover from potential disaster.


Although backing up your data is strongly recommended by computer authors, experts, and support personnel, it is a task that many Mac users never do for a variety of reasons. Some people don't back up data because they think their systems are infallible and won't crash. Still others are confused about how to make a backup of their system, or they lack the hardware and software necessary to maintain good backups. And then there are always those who simply don't believe that protecting their data is enough of a priority to waste their time on it.

However, because you are reading this book, I assume that you are serious about your Mac and recognize the value of a good backup system.

There are four steps to creating and implementing a solid backup system. These steps are the following:

  • Define a strategy You need to define your own backup strategy; your strategy should define the types of data you will back up and how often you will back up your data. These choices will guide you as you decide on the type of hardware and software you use.

  • Obtain and learn to use backup hardware You need some kind of hardware on which to store the backed-up data. Many types of hardware can be used, including tape drives, removable media drives, additional hard drives, DVD-R drives, or CD-RW drives.

  • Obtain and learn to use backup software Ideally, you should use some sort of software to automate the backup process. The easier you make it on yourself, the more likely it is that your backup system will work reliably.

  • Maintain your backup system Like all other systems, you need to maintain your backup system and ensure that your data is safe.

Defining a Backup Strategy

One of the first things you need to decide is what data on your machine will be backed up.

The three general categories of data you should consider backing up are

  • Documents, photos, movies, music, and other important data you create or purchase These items are, after all, the reason you use a Mac in the first place. You will want to back up all your own data because it doesn't exist anywhere other than on your computer. If you lose important data, it might be impossible to re-create. Even if you are able to re-create it, you will be wasting a lot of valuable time redoing what you have already done. Other data, such as your photos, simply can never be re-created. Still other data, such as music you have purchased from the iTunes Music Store, will cost money to replace.

  • System files You should have installation discs that contain your Mac OS software, so you usually don't risk losing the Mac OS software itself. What you do risk losing is any customization you have done, updates you have installed, and so on. If you have adjusted any settings or added any third-party software, all the settings you have changed will be lost in the event of a major failure.

    Additionally, don't forget about all the configuration information you have on your machine. For example, if you lose your system for some reason, you might lose all the configuration you have done to make your Mac connect to the Internet. You might also lose all the serial numbers of your software, which you will have to reenter if you need to reinstall it.

  • Applications and other third-party software As with the OS software, you probably have discs containing much of your third-party software. What you lose if you have a failure without a backup is the customization of those applications. Plus, you will have to reinstall that softwarenot an easy task if you have a lot of applications installed on your Mac. In any case, it can be very time-consuming to reinstall your applications. Don't forget about all the updates you have applied to these applications. If you lose your system, you'll have to do that all again, too.

NOTE

These days, you probably obtain a lot of your software by downloading it from the Net. If you lose the installers or patches you download without having a backup, you will have to download them againassuming they are still available, of course. Sometimes, the version you want to use has been replaced by a newer version you don't want to use or pay for. (In my opinion, software companies should make older versions of applications available to download to handle cases where you need to reinstall it, but not all of them do.) And, occasionally, software moves from shareware to commercial, in which case it becomes unavailable to download again without paying for it. You should keep backup copies of any software installers or updates you download so you can reinstall that software if you need towhether it is still available from the original source.


In conjunction with the kind of files you will back up, several types of backups you can make include:

  • Full backup In a full backup, you back up each and every file on your system. The advantage of doing full backups is that restoring your entire system, as well as just particular parts of it, is possible.

  • Selected files only Using this scheme, you select particular files to back up; usually these are your important data (documents, photos, music, and so on) and some of your customization files (for example, preferences files). The advantage of this scheme is that you can make a backup quickly while protecting the most important files on your computer.

  • Incremental backup This scheme combines the first two techniques in that all files are backed up the first time, but after that, only files that have changed are backed up until the next full backup. This scheme protects all your files but avoids the time and space requirements of doing a full backup each time.

What you decide about the type of data you will back up and how you will back it up should determine the type of backup system you develop and use. For example, if you decide that you don't mind having to reinstall applications and reconfigure settings or you mainly use small document files, you might be able to simply copy your document files onto a CD-RW or other removable media drive. If you have a great deal of data to protect, you will need to implement a more sophisticated system.

If you can assemble the hardware and software to do incremental backups, you should use this approach. It is the only one that is practical for frequent backups and also protects all your data.

Ideally, you want your backup system to work without any supervision or intervention by you. This is called an unattended backup because you don't even need to be there for the system to work. You can set the system to automatically back up during times when you are not working on your Mac. This is not only convenient, but it also means that because you don't have to do anything, you can't forget or be too lazy to keep your backups up-to-date.

Choosing Backup Hardware

The hardware you use for your backup system is important because having hardware that doesn't match the types of backups you want to make will doom your backup plan to failure. For example, if you go with a dedicated back-up hard drive or tape drive, you will be able to do frequent, incremental backups. The easier and better you make your backup system, the less work you have to do with it, and the more likely it is that you will do the backups. Table 35.1 lists the major types of backup hardware and summarizes their advantages and disadvantages.

Table 35.1. Backup Hardware

Drive Type

Backup Capability

Advantages

Disadvantages

CD-R and CD-RW

Can handle large amounts of data for full and incremental backups.

Drive has multiple uses (mastering CDs for distribution, creating audio CDs, and so on).

Data is easy to share and recover because all computers have CD-ROM drives. Provides nearly permanent storage; this is a good choice for archival purposes.

Backups can be stored away from your Mac.

CD-RW drives are standard on all modern Macs. Media is very inexpensive.

Capacity of individual discs is limited so unattended backups are not always possible.

Relatively slow.

DVD-R and DVD-RW

Can store large amounts of data on each disc.

Even so, you can't store enough o make full, unattended backups in most cases. Media can be mounted in most Macs.

Data is easy to share because most computers can read DVD discs.

Provides nearly permanent storage; this is a good choice for archival purposes.

Backups can be stored away from your Mac.

Apple's SuperDrive is available on all Mac models.

DVD-R and DVD-RW drives can be used for many purposes (burning DVD movie discs, restoring disks, and so on).

DVD-R media is not reusable.

Media is relatively expensive for backup use.

Relatively slow.

Hard drive

Depending on size, can handle large amounts of data for unattended full and incremental backups.

Very fast.

Data is easily accessible.

Drive can be mounted and used for other tasks.

Backup drive is likely to be used for other purposes and thus might not be available for backing up.

More difficult to store backups away from your Mac.

Relatively high cost per MB of data storage.

Data is harder to share.

Unlikely to have sufficient storage space to make full backups unless you purchase a dedicated backup drive.

  

Backup is subject to power surges and other outside causes of failure.

Capacity can't be expanded.

 

Removable media (Zip, Jaz, SyQuest, and so on)

Depending on the drive type, can handle small to medium amounts of data.

Drives can be mounted and used for work as well as for backups.

Can be used to easily share data with others.

Backups can be stored away from your Mac.

Unlikely that a single disk will hold all the data on your Mac so full, unattended backups aren't possible.

Magnetic storage devices can be affected by magnetic forces and will degrade over time Many lower-capacity disks (such as 250MB Zip disks) are required for large amounts of data.

Few Macs have these drives.

Tape

Can handle large amounts of data for full and incremental backups.

Large storage capability is perfect for unattended backups.

Media is inexpensive (for example, a Travan 20GB tape costs as little as $34).

Backups can be stored away from your Mac.

Difficult to share with others because a tape drive of the same format must be available.

Tape can't be mounted; a tape drive is a single-purpose device Tapes can be affected by magnetic forces and degrade over time Relatively slow.

Drives can be expensive.


Table 35.1 lists many options, but a careful review of the table should reveal that there are really only four choices for a serious backup system: tape, hard drive, DVD-R, or CD-RW.

The following sections explains how I rate these options, in order of preference.

External FireWire Hard Drives

Using a hard drive for backup provides the fastest performance, and you can usually get a drive large enough to store all the files needed to back up your primary drives (see Figure 35.4). You can easily configure automated backups so your data is constantly protected with no intervention on your part. And with FireWire, installing and using an external hard drive is literally a matter of connecting power to the drive, connecting the FireWire cable, and turning on the drive. That is all there is to it. Using a FireWire drive is simple. For performance and ease-of-use, a hard drive can't be beat.

Figure 35.4. The LaCie 500GB FireWire hard drive provides excellent performance and lots of room.


There are several significant disadvantages to using a hard drive to back up data. One is that you can't archive data on a hard drive; a hard drive can be used only for your current backups. Another is that you can't store the backup in an alternative location, nor can you create multiple backups (unless you want to invest in multiple drives). Still another is that the capacity of the drive is fixed; the only way to expand the capacity of your system is to add more drives. And, hard drives can fail due to the same reasons that a drive in your Mac can fail, in which case your backup becomes worthless.

Another downside is that you will be tempted to use the backup drive for additional purposes when your other drives get full. You might delete the backup "temporarily" while you work on another project. Guess when something will go wrong and you will need your backup?

Still, even with these drawbacks, I find a hard drive the most convenient option for daily, incremental backups.

Tape Drives

From a purist's viewpoint, this option wins by a mile. When it comes to the sole function of backing up, nothing comes close to a tape drive. Because the capacity of each tape is so large, a single tape drive can handle unattended backups for all but medium or large networks (in which a more sophisticated system is required). And the media for a tape drive is relatively cheap, can be reused, and is portable.

The downside of a tape drive is that it serves a sole purpose, which is backing up (of course, this is also a positive because you won't ever be tempted to use it for something else).

Tape drives are available in many format and interface options, but they all work in a similar way. If you want the best backup system, consider adding a tape drive to your Mac.

DVD-R Drives

DVD-R discs provide a good amount of storage space on each disc (4.7GB). This is enough room to do full and incremental backups, although you probably won't be able to store an entire backup on a single disc. Another plus is that many Macs include a SuperDrive so you don't need to spend money on additional hardware to back up your system. DVD-R is an excellent option for archiving data and should provide good long-term storage for the data you don't need to work on any longer.

Of course, a DVD-R drive is also very useful for other purposes, such as for creating DVDs with iDVD.

CD-RW Drives

This option takes a distant fourth place, in my opinion. These drives are also useful for backup purposes because CD-R media is so inexpensive (about $.50 or less for 650MB) and because many Macs have a CD-RW drive built in. Plus, there are many other ways to use a CD-RW drive, such as creating audio CDs. Because every computer has a drive that can read CD-R discs, the data is very accessible.

However, even with these benefits, CD-RW drives are not an optimal choice for backing up. This is primarily because a CD holds only 650MB of data. Although that is a significant amount for everyday documents, it is inadequate for some types of projects. For example, when you consider iMovie projects, a single disc usually can't hold even one project. This means that unattended backups are usually not practical. Backing up an entire system on a CD-RW drive can take a long time, and you have to be there to swap new media in and out. And then, you have to manage the many discs that are required for your backups.

Still, if you already have a CD-RW, it is a good way to get your backup system started and to at least back up your documents.

Choosing Backup Software

Backup software enables you to define which files will be backed up and how often the backup will be updated. It also enables you to restore your data when the time comes. The software should enable you to automate the process as well.

Although there are many choices on the hardware side, when it comes to backup software there are really only two options. The best option for Mac backup software is EMC Dantz Corporation's Retrospect. If you are a .Mac user, you can get a copy of Apple's Backup for free. Though not as good as Retrospect, it is a fairly capable application.

NOTE

Note that Retrospect comes in various flavors depending on what you are backing up. Retrospect Express Backup is targeted to individual users with relatively simply backup needs, whereas Retrospect Workgroup Backup can back up a networked workgroup.


Retrospect does only one thing: It helps you create, implement, and maintain backups. Although limited in scope, Retrospect excels in function; it is a must-have piece of software. It is easy to use, yet it includes all the functions you need to establish and automate your backup strategy. If you intend to back up your Mac in the most effective way possible, you simply must use Retrospect.

Unfortunately, I don't have the space to explain how to use Retrospect, but suffice it to say that this software is extremely well designed and excellently implemented. After you install and configure it, it is so good that you won't have to deal with it very much (which should be a goal for any backup system).

Even better, many tape and other backup drives include this software, so you get everything you need for your backup system in one package.

To learn about EMC Dantz and Retrospect, check out www.dantz.com (see Figure 35.5). You can get your questions about backing up your system answered there. I have been a customer for years and have been amazed by the exceptional support this company offers.

Figure 35.5. When it comes to Mac backup software, EMC Dantz's Retrospect is as good as it gets.


If you have a .Mac account, you can download and use Apple's Backup application. This application provides good backup capabilities. In addition to being able to back up to CD or DVD, you can back up your files to your iDisk (which takes the idea of remote storage of your data to a new level). You can also automate your backups. The application is simple to use and is free to anyone who has a .Mac account.

To learn about Backup, visit www.mac.com. If you have a .Mac account, you can download a copy of the software for free.

Using a Backup System

I can't emphasize enough how important it is to maintain good backups for your data. Here are a few tips to keep in mind:

  • Develop your own strategy based on the hardware and software you have or can afford to purchase At the least, make sure your critical data files are protected.

  • Make sure that backing up is easy If you have to do a lot of work to back up or if it takes a lot of your time, you won't end up keeping up-to-date backups. Ideally, you want to be able to do unattended backups; a hard or tape drive and a copy of Retrospect are your best bet.

  • Be consistent Whatever strategy you decide on, keep up with it. Old, out-of-date backups are not much better than no backups.

  • Always refresh your backups before you install any new software or make major changes to your system This will enable you to recover data if the changes you make to your system cause problems.

  • Be sure to test your backups regularly Try to restore a file or two to ensure that everything is working properly. If you don't, you might get a nasty surprise when you really need to restore some data.

  • Maintain your equipment Almost all equipment needs some kind of maintenance now and again, so follow the manufacturer's guidelines to keep your system in top condition.

  • Maintain more than one set of backups Create multiple copies of your backups in case something happens to one set.

  • Keep a set of backups offsite Keep a copy of your backups in a different location than your Mac is in. This will save you in the event of a catastrophic event such as fire or theft.

NOTE

Archiving is slightly different from backing up. Backing up is done mostly for the "active" data on your Mac, whereas archiving is done with data you don't really need to work with anymore. Fortunately, you can use your backup system to archive data as well. For archiving smaller documents, a CD-RW drive is a good choice because the media is very cheap and relatively permanent. For larger amounts of data, a DVD-R disc is a good way to archive. When you archive, you should use a solution that won't degrade over time. In this case, an optical media is a better choice than magnetic media, such as a tape.


Restoring a Disk or Files

Using Disk Utility, you can create and save a disk image of a folder, volume, or disk. (A disk image is a file type that can be mounted and used just like a physical volume, such as a hard drive.) You can then use Disk Utility's Restore feature to restore the entire volume or specific files that are part of that disk image. This is, in effect, backing up specific parts of your system. You can choose folders, volumes, or an entire disk. To do this, you first use Disk Utility to create a disk image of the volume or folder you want to back up.

When you need to restore a file, you select the disk image you created and use the Restore tab to restore it or specific files it contains.

Although this approach has the benefit of using tools always available under Mac OS X, it does have several major drawbacks. This first is that you have to manually update the disk images you save. The second is that you still have to have the space to store those images (of course, you don't want to store them on the same volume as the files they include). However, you can use this technique to back up files if you don't have a better solution or to archive them. For example, you might want to use this technique to archive your iTunes music files, especially those you've purchased from the iTunes Music Store.




Special Edition Using MAC OS X Tiger
Special Edition Using Mac OS X Tiger
ISBN: 0789733919
EAN: 2147483647
Year: 2003
Pages: 317
Authors: Brad Miser

flylib.com © 2008-2017.
If you may any questions please contact us: flylib@qtcs.net