Time Machine

  Time Machine is a phenomenal feature of Mac OS 10.5 (Leopard). In fact, because of that feature alone, I recommend that most people upgrade their machines to Leopard. Time Machine is an automatic backup program that is built into the OS. But unlike most backup programs, this is tremendously robust and extremely simple to setup and use.

Features:

• Full system Backup- Time Machine will automatically backup your entire system including the OS, applications and user data.
• Incremental Backups- After the full backup has completed, Time Machine will incrementally backup your system on an hourly basis so that all changes are recorded. This allows for a quick and complete backup.
• File Version Restore- You can restore a particular version of any file by "going back in time" even if the file has been saved over multiple times.
• Whole System Restore- In the event that your hard drive fails completely and needs to be replaced, you can restore your complete system (OS, applications and user data) from a Time Machine backup

System Requirements:

  All that is required for Time Machine is that your computer be running Leopard (so upgrade now) and an external hard drive or network drive (Time Capsule is specifically designed for this, too).

How To:

  The first time you plug in an external hard drive (USB, firewire, xsan or eSATA), Time Machine will ask if you want to use this drive as a Time Machine backup. If you click "Yes", Time Machine will automatically backup our entire system. Once that is complete, it will begin incrementally backing up your system on an hourly basis. The larger the hard drive you use for Time Machine, the further back into time you'll be able to go because it can store more information. When the drive is almost full, Time Machine will begin to delete the oldest files first in order to make room for the newest files that you're creating. This will give you the most up-to-date backup possible. It is generally suggested that you purchase a drive that is double the capacity of your startup volume. Time Machine can only backup the startup volume and will not backup any external drives or secondary internal drives.

  Your Time Machine backup must be formatted as a Mac OS Extended or a Mac OS Extended (case-sensitive) volume. If it is not already formatted this way, it will tell you that it must be reformatted. Please keep in mind that reformatting a drive destroys ALL of the information on that drive. To learn how to format a drive, refer to the article on Disk Utility.

  You can use one drive to backup multiple systems with Time Machine. Leopard Server also allows you to use Time Machine to backup a group of networked client machines to the server.

  To restore a single file from Time Machine is simple. You can either do it manually through the Finder and navigate your way to the Time Machine volume and to your computer's backup, locate the file and copy it to the desired destination or you can use the Time Machine interface to assist you. To use the Time Machine interface, simply enter Time Machine. Either select that from the pull down menu item in the menu bar or open the application from within the Applications folder.

  Mail, iPhoto and Address Book are special applications when it comes to restoring data because they are database programs. However, Apple has made this easy for us. Simply go into any one of these programs and then enter Time Machine and instead of being confronted with a Finder window you'll be confronted with either your Mail window, iPhoto window or Address Book window (depending on which program was in focus at the time you entered Time Machine). Now you can pick out the exact item (either a particular email, a single photo or a single address) that you want restored. Simply hit the restore button on the bottom right and the item will be restored. It's that simple.

Best Practices

  There are a few things that you should know so that your backups are efficient and quick. First of all, not everything needs to be backed up. You can exclude these items by going to the Apple Menu > System Preferences > Time Machine and adding those items to the "Exclude" list. I suggest not backing up your "Cache" folder that is located in you "Library" folder. I also do not back up items in the "Downloads" folder. If it is something worth keeping, I'll officially install it or move it to a more appropriate location.

  Databases are a very peculiar kind of file. If you use Thunderbird or Entourage as your email client, you might notice that these applications are really database applications. That is, all of your emails are part of a database- they are not individual files. So, while Entourage is open and collecting email, that database is constantly changing. That means Time Machine will constantly be backing up that single database file. If you maintain a long history of emails, this file can grow to be as large as 2 or 3 GB! Imaging trying to backup a 3 GB file every hour. Time Machine does not see that "most" of the file is the same and that only a few emails were added to it; it just sees that the file has changed and must now backup the entire file! Not only is this very inefficient but it will slow your computer down, it will slow your network down and your backup drive will become full in no time! You MUST exclude these kinds of files from being backed up. This means that you'll have to find another way to backup your email. OR, just use Apple's Mail program as an email client. With Mail, each email is its own file so any new emails are simply added to the backup- it isn't backing up all of your email every hour. If you have any kind of database program that changes often, you should probably exclude that as well. That may include Filemaker databases, iPhoto or Aperture if you are constantly doing work in them (like a photographer).