Back It Up Part 1

No matter how reliable your Mac has been, you need a plan for backing up your data. At some point a hard drive will fail, you’ll delete an important file or just do something stupid as I did recently. When that happens you’ll be glad you had a backup. Lets look at some of the things you need to consider in developing an effective backup strategy. In the second part of the series we’ll look at some of the tools available for backing up your Mac.

Archive, Backup, or Clone

Early on in developing a backup plan, you need to think about whether your data needs to be archived, backed up, or cloned. This decision affects how much storage space you need and to some extent the type of media that will be used. Let’s start by defining a few basic terms so everyone’s on the same page.

When I refer to an archive I mean a method of backing up data that includes the current version of a document and preceding versions of the same document. Suppose you’re in the midst of writing the “Great American Novel” and you delete a paragraph from page ten. Later you decide that this paragraph was brilliant and you’d like to use it after all. If you’ve kept an archive with the novel in it, you could go back to the first draft and get that quote.  That’s why I think of Apple’s Time Machine as more like an archiving program than a backup program. It keeps your current information and as many previous versions of the data as it can fit in its available storage space.

For me, the term backup refers to a copy of a file. Typically a backup keeps only the most recent version of a file. It’s a bit like making a photocopy of your novel. When you’re finished, you have a snapshot of your novel at a specific point in time. The same holds true for your digital files. The caveat for most backups is that unless you take steps to name each copy of the file differently you can’t go back to the very first backup to retrieve something. Once a backup file is written, its information replaces what was there previously.

A clone is, of course, an exact copy of something. A backup could by some accounts be considered a clone because it is a copy of the original file. In the computer world a “clone” is an exact copy of your boot drive (Mac cloning tools omit a few files that get recreated by the OS). In an emergency you can boot your computer from the clone and get back to work immediately. Without a clone you’ll need to either boot from an emergency CD or partition and reload programs and data from a backup.

What Files and How Much Storage Space Do I Need? 

This can be a difficult question because it depends in part on how much data you need to backup. In short, “how much data are you willing to lose if your drive fails?” You’re the only one that can answer that question. Finding the answer often means deciding what you need to preserve, what you want to preserve, and what doesn’t need to be preserved at all. You need the several years of business records, and want the years of irreplaceable family photos and videos so those are files that need to be backed up. Do you really need the massive collection of video downloaded from the internet? I’ll leave that decision up to you.

While you are thinking about what to back up don’t forget about information that is “in the cloud”. The last time I cloned my system I included purchases from the App Store in the clone. To be honest it never occurred to me not to include those programs.  I could just as easily have logged into my account and downloaded the programs again but chose not to do so. Obviously, the speed and reliability of your internet connection is going to be an important consideration here.

In addition to those photos, personal records, and other data you’ve just chosen to back up, are you going to clone your entire system periodically? Answering yes means you’ll need more space than if you are just backing up data. Whatever you choose to include in your backup, start looking at the total amount of space it occupies and think in terms of a backup being one and one half to two times larger at a minimum. This gives you a little room to grow. If you are cloning your hard drive, the backup drive doesn’t have to be any larger than the disk you want to backup.

The Choices Seem Endless – Hard Drives, Discs, Online Storage

OK, you understand the need to back up your files and you have some idea what you want to back up but where are you going to put the backup? I mean, are you going to use one or more hard drives, optical discs (CD/DVD/Blu-Ray), or some type of online backup service? Post this question on our forums and you’ll get lots of pros and cons for each method. Your primary concerns are cost per gigabyte, reliability/durability, and convenience.

When you are calculating the cost per gigabyte, make sure you are considering current information. The cost of hard drives, for example, may vary depending upon the drive interface (USB, Firewire, SATA, etc.), its capacity, and to some extent the speed of the drive in question. You’re going to pay something of a premium if, for example, you insist on the fastest possible drives. On a positive note, modern hard drives cram a lot of storage capacity in a relatively small physical space. Backups to hard drives also have a certain amount of convenience to them. Because they are sold in fairly high capacities you can usually start the backups and walk away without worrying about the need to change disks mid backup.

Optical discs (CDs/DVDs/Blu-Ray) all share similar characteristics as far as backups are concerned. Each type of disc is relatively durable when properly stored. With the exception of Blu-ray discs, data can be burned to the media with software ranging in price from free to relatively expensive. For CDs and DVDs, there is little or no additional hardware costs since the burners included with modern Macs can handle burning and playback of CDs and DVDs. Blu-ray discs are the exception here. Burning those discs on a Mac requires the purchase of a Blu-ray capable burner and appropriate software. I’ll leave it up to you to decide if Blu-ray’s potential for storing up to 50 GB of data is worth it compared to the just over 9 GB for dual layer DVDs.

Online backup services are also a viable option for some users. In this case data that the user selects is backed up to a provider’s servers. Generally speaking these services require the user to install an application that is used to select which files are backed up. Once files are selected for inclusion in the initial backup, they are monitored for changes so that the backup is automatically kept current. Obviously, the pros to this approach are that backups occur in the background and generally occur unobtrusively once the initial backup is complete. In most cases the maximum size of a backup is either sufficient for most users or can be increased by paying an additional fee monthly or annually. Finally, this type of backup automatically provides the benefits of “off site” storage. If fire, flooding, or other disasters damage the backups you have at home, the online backup is still available.

There are some drawbacks to online backup services. The initial backup can take quite some time due to the amount of data being transferred. Not all accounts with these services cover all types of files. If you’re interested in backing up video files, applications, or system files make sure those files are part of your plan. Some services will back up these files but only as part of plans available at additional cost. If you’re going to use an online backup service make sure you understand the plans available, what they cost, and how long you have to retrieve your data if you decide not to continue your subscription.


There isn’t one right answer to the aforementioned questions. Your needs and tolerance for data loss may be different from mine. Most good backup plans may include more than one of these elements and may change over time as your needs change. Stay tuned for part two of this series when we take a brief look at Time Machine and some of the other backup software that’s available.