Computer Backup 101: Not-so Random Thoughts About Mac Backup
Why Backup?
Losing data is a drag. Many of us store digital photos, original documents, calendaring and contact information, architectural drawings, spreadsheets, video and music on our computers. This data can be irreplaceable if your computer is lost or stolen, or if your hard drive fails.Many computers store data which is constantly changing -- files such as calendars, databases, email, etc. A hard drive malfunction can cause loss of everything since your last backup - that means loosing everything if you’ve never backed up.
Quick and Dirty Steps to Backing up your Mac
If you're already convinced and just want to make a backup without reading my ramblings below, just follow these steps:
- Buy an External FireWire hard drive with at least the capacity of your computer's hard drive. I like FireLite drives from SmartDisk.
- Download and install SuperDuper - it's free for basic backups!
- Launch SuperDuper - Select your hard drive's name from the "Copy" pop-up menu on the left. Select the external backup drive from the "To" pop-up menu on the right.
- Click the "Copy Now" button!
Need more convincing or details? Read on...
The Software Update Conundrum
It is not uncommon to open your computer or launch a program and have it ask if you want to download and install a software update. This isn't always a good thing...Most software updates fix bugs, add features and make programs more stable. Other software updates introduce new bugs, make programs crash more often and can even cause data loss.
For example, an update to a popular anti-virus program caused some users to lose email messages when the program misidentified some messages as a virus and permanently deleted them. Oops.
I have also seen Apple's automatic Software Update system updates go awry, leaving a user's computer in an unusable state.
Making a backup (preferably a Bootable backup) before performing a software update protects against buggy software updates. (See the Software section below for information about making a 'Sandbox' backup to make un-doing a software update simple). More information and suggestions for performing software updates are here.
Bootable Backups
A bootable backup is an exact copy of your hard drive. With all of your files, operating system and everything else backed up, you can plug your backup drive into any Mac with a similar processor and a FireWire port and actually boot from it. This will have you up and working again in minutes*.Where this won't save your data:
1. If you accidentally delete a file and then run your backup, the file is gone.
2. Data corruption. Backing up a FileMaker database with bad data yields bad data on the backup.Use an archival backup system (see below) to protect against these types of problems.
*Note: Intel Macs can't be booted from a backup made from a PowerPC mac and vice versa. The operating system files are different.
Archival Backup
An Archival backup system keeps copies of your changing files every time you run a backup. You can't boot from an archival backup, so this type of backup should be used as a method of damage control for lost, accidentally deleted or corrupted files or folders, not immediate recovery.This type of backup is ideal if you realize that one afternoon three weeks ago, the cat took a nap on your keyboard and erased two hours worth of client notes you'd entered. You hadn't noticed the data was gone until now and since many programs auto-save, you were never asked if you wanted to save Fluffy's "changes."
Archival backups do not help if you need immediate recovery and/or bootability of your computer.
Leopard's Time Machine:
A new feature called Time Machine in Mac OS X 10.5 provides archival backups to an external hard drive. If you're running Leopard, you don't need any third party software to run archival backups nightly. These backups allow you to restore a version of a file from a previous date in the event of corruption or accidental deletion.Note: Time Machine is designed to backup to only one external disk drive. This makes a good local backup, but does not allow for storage of data off-site.
Also note: you can't boot your computer from a Time Machine backup. This means that it could be hours before you're able to access your data in the event of a hard drive problem.
Why Should I Backup Everything, Not Just My "Important" Files?
As computer users, we spend more and more time installing and configuring software, setting up printers, customizing programs and organizing images and files into albums or folders. Hard drives are cheap these days and backing up everything will save your organization as well as the data you're organizing.Imagine This Scenario...
Your laptop is stolen (God forbid) or your office computer burns up in a fire (Gasp). If this were to happen, you‘d need to access the data files you’d previously backed up.Let’s say these were some important Word documents or your calendar. These data files are pretty useless until you accomplish these tasks:
1. Purchase/borrow a computer
2. Find/purchase a device which will read your backup media (tape drive, floppy drive, CD, DVD, etc.). Purchase/locate appropriate cables for device. Skip this step and go to the head of the class if you follow my advice below and buy a bus-powered FireWire drive.
3. Restore the files to the new computer
4. Find original Word or calendar program installer disks. Find software registration codes. Install software.
5. Apply appropriate software updates for Word.On top of not being much fun, with a data only backup you’ve lost nearly EVERYTHING else on your computer, including the applications, your email archives, web site bookmarks and those cute digital pictures of Fluffy the cat napping on your keyboard.
Consider this scenario instead:
1. Purchase/borrow a computer
2. Plug external FireWire drive into computer.
3. Reboot computer.
Everything is where you expect it. Files are located in the folders where you’re used to seeing them. Your software is up-to-date and serial numbers are already installed. Your email is complete, address book intact. You’ve only lost any work you’ve done since your last backup (<24 hours if you backup daily).
4. Work in this mode until you have time to copy everything back to your internal drive.Get Outa Here!
The most important thing you can do if you are concerned about theft, fire flood or any range of natural or man made disasters, is to get a backup off-site regularly.Whether you use a Bootable or Archival backup system, you should have at least two storage devices, and should rotate one off-site frequently (i.e. every week).
For example, I take my MacBook Pro with me to work every day. I leave my backup drive at home, just in case my laptop is lost or stolen (sniff) while I’m out in the world. If the house burns down while I’m out walking the dog and my computer and backup drives go up in flames, life gets more challenging.
So...we also rotate archival backups between two different disks so one is always off-site. We backup to one drive for a week and then store it off-site for a week while we backup to a second disk. In a worst case scenario we would only loose one week's worth of work.
.Mac, iDisk and Backup
If you have a .Mac account, you can use the 10 gigabytes of storage space on your iDisk to backup specific files or folders by dragging them to your iDisk as needed to make off-site copies. Choose Go>iDisk>My iDisk in the Finder to connect to your iDisk. An icon (as shown below) named with your username will appear on your Desktop onto which you can drag files.
iDisk iconApple also provides a backup program called (you guessed it!) "Backup". With Backup and a .Mac account you can schedule times to automatically send selected files/folders to your iDisk on the .Mac servers. There isn't enough space on your iDisk to copy an everything on your hard drive, so consider this a good way to get some of your mostimportant data off-site on a regular basis. Use this in conjunction to, not instead of a bootable backup. You can also use Backup to run archival backups to an external hard drive.
What Hardware Do I Need to Backup My Computer?
I recommend backing up to an external hard drive. They’re fast, relatively inexpensive, have the capacity to hold your entire hard drive and are quite reliable.External hard drives are available with several different interfaces (how they connect to the computer) including FireWire and USB. To make things more confusing there are two flavors of each; FireWire 400 and FireWire 800 as well as USB 1.1 and USB 2.0.
I generally recommend external FireWire hard drives vs. USB drives because you can boot all Mac computers from most FireWire drives. Intel based Macs can but boot from USB drives but PowerPC Macs can't. Since there isn't a significant price difference, go with FireWire for maximum flexibility. A FireWire 400 port has shipped on all Apple machines (including laptops) since early 1999, so you shouldn't have any trouble connecting the drive to your computer if it's relatively new.
A FireWire drive to backup your computer starts at around $110.
More About FireWire
If you plan on storing a backup off-site and/or want a simple plug-and-play backup, I recommend using a FireWire bus-powered hard drive. These don't require any AC power cables - they get their power from the Mac's FireWire port.This makes data recovery easy in case your computer/cables are damaged in a disaster. Just connect a bus-powered drive with a standard, available-at-any-computer-store FireWire cable, reboot and you're ready to go.
Here are some examples of bus-powered FireWire drives:
These drives and many others are available at the Apple Store - both online and at retail locations. I've also had good experiences with LaCie brand drives.
What Capacity Drive Should I Purchase for Backup?
Generally speaking, if you want a bootable backup and your computer has a 80GB hard drive, purchase a 80GB backup drive.The exception to this rule is if you have a large hard drive and don’t think you’ll ever come close to filling it up. See below on how to determine if this is the case.
How Do I Determine the Capacity of my Hard Drive?
Select (click once) on the hard drive icon on your Desktop and choose ‘Get Info’ from the File menu. You should see something like this:
Look at the ‘Capacity’ to determine the size (in Gigabytes) of your drive. Then look at ‘Used’ and ‘Available’ to see how much space your data is actually consuming and how much space is free for storage of additional documents, music, pictures, etc.
If you own a digital camera, plan to import music from CD’s and/or downloads or have any plan to edit video on your computer, expect the total amount of data on your hard drive to grow somewhat rapidly. Plan for a backup drive with suitable capacity to hold all of your data now, plus some significant growth.
For example, in the picture to the left, the ‘Used’ on my drive is close enough to the ‘Capacity’ that I’d want to purchase a 60GB drive to backup everything on my 60GB internal hard drive.
If the main use of your computer is for email, surfing the web and writing some Word documents, your hard drive data won’t grow very quickly and you can purchase a smaller (less expensive) hard drive for backup.
Remind Me Again...Why Bus-Powered FireWire Drives for off-site backup?
1. Consider the fire scenario above. You might have a hard drive with a great backup, but it’s useless unless you have the power supply cable. An extra power cable might be available from the manufacturer, but it would take some amount of time to get one. Meanwhile your data is locked up on the powerless hard drive.2. They’re small enough to carry to an off-site location and don’t weigh much.
If you have more than one non-bus-powered hard drive, make sure to store one of the power supply cables off-site with the off-site drive!
Why Do I need a Software Program to Backup My Computer?
Three reasons:
1. Mac OS X (the operating system that runs your Mac) is based on UNIX. Some files are not available to the user and therefore cannot be copied by standard copy methods such as dragging files in the Finder. Attempting to copy a hard drive by simply dragging it's to another drive does not yield a complete backup (like it did in OS 9). Some files simply won’t be copied and the backup will not start up another computer. Using a backup program makes sure that ALL files get copied to the backup drive, making a fully bootable drive that can start up another Mac (i.e. a new machine or loaner in the event of an emergency).
2. Time. By doing something called an incremental backup, the backup program only backs up files that have changed or are new. This means a backup only takes 2-10 minutes instead of several hours or more.
3. Automation. Some backup programs can run unattended backups automatically. Nightly backups, while you sleep, are a good thing.
Backup Software
For bootable backups, I recommend SuperDuper!. I know, I know - silly name but it's a great product with a reasonably clean user interface and it only costs $27.95. SuperDuper!'s 'Smart Update' option can greatly reduce the time required to complete backups by copying only files which are new or have been modified, rather than recopying everything on the drive.Another great feature of SuperDuper! is something they call a 'Sandbox'. The idea is that you can create a bootable copy of your operating system, stored on another hard drive so you can install a software update for testing. If the software update is buggy or makes one of your programs misbehave, all you have to do is reboot and the software update is 'undone'.
For Archival backups and backups of computers over a network I recommend Retrospect. This program is the de facto standard for archival backup, as well as the poster child for unintuitive user interface.
You can also do some fancy backup-like stuff with a program called SoftRAID. See the section on mirroring below for more information.
TEST Your Backups!
It is crucial to make sure the data on your backups is useable - before you're in dire straits.If your backup is a Bootable backup, try booting from it. Try booting other computers from it. Make sure it does what you expect. It's easier to fix a problem now when your data is available.
If you have a Retrospect backup, try restoring some data (you might want to practice restoring stuff with Retrospect - the interface is a bit clumsy and unintuitive).
Backing up an Intel Mac? There's one more thing...
If you're making a bootable backup of an Mac with an Intel processor, you've got one more step to do. To boot an Intel machine, you'll need to re-partition your backup drive in a special way called 'GUID Partition Table'. If you neglect this part, your files will reside on the backup drive but you won't be able to actually boot from it.WARNING: The steps below will permanently erase the backup drive!
1. Open Disk Utility (Applications: Utilities: Disk Utility) and select your backup drive from the column on the left. It will be named something like "111.8 GB SmartDisk". If you make a mistake and select the formatted volume name such as "FireLite" in the list, the Options button will be grayed out and you won't be able to do the next step.
2. Click the Options button at the bottom of the Disk Utility window.
3. Choose "GUID Partition Table" button and click OK to close the window.
2nd WARNING: The step below permanently erases the drive!
4. Click the "Partition" button in the lower right corner of the Disk Utility window. The drive will be erased and partitioned as GUID. Launch your backup software and run a backup. To test for bootability by holding down the Option key while your Mac reboots.
Information on Drive Formats
Many USB and FireWire drives are sold as devices formatted for Windows computers. Cleverly, the Mac can read these drives, but in my experience, you're asking for trouble if you try to store much data on a Windows formatted drive. Here's how to reformat the disk as "Mac OS Extended (journaled)" for use with your Mac:WARNING: The steps below will permanently erase the backup drive!
1. Launch Disk Utility (see above for location)
2. Select the backup drive from the list on the left
3. Select "Mac OS Extended (journaled)" from the Format pop-up menu
4. Click the Erase button
Drive Mirroring (RAID):
You can configure a system where data is written to a second (or third) hard drive(s) simultaneously. This type of backup system is called 'drive mirroring' and helps reduce data loss in the event of a mechanical hard drive failure. For mission critical machines and servers, the mirroring software can even sense that the main drive has failed and switch to the backup drive.Mirrored backup systems are created using special software which creates and monitors the mirrored disks (also known as a Redundant Array of Independent Disks or RAID). Apple includes some rudimentary RAID functionality in Disk Utility, but SoftRAID has an intuitive user interface and is much more reliable. SoftRAID is also optimized for performance on servers and has many, many more features - too many to address here.
What to store Off-Site
Here's a list of stuff to make sure you store off-site:
1. Hard drive, rotated frequently so the data is current
2. FireWire or other data cable to connect your backup drive
3. Backup software installer, updates and the serial number/install code
4. Power supply cable for your backup drive (if using non bus-powered drives)
5. Application serial numbers or install codes for critical programs.Network Backups
Backing up more than one computer over your network is more than can be covered in the scope of this document.Please feel free to contact me for more information on hardware and software recommendations for Macintosh backup systems.
LANsharks Consulting - 510-601-5475
About the Author:
Kirk van Druten is the owner and founder of LANsharks Consulting, a Macintosh network and consulting firm, serving Northern California clients since 1994.© Copyright 2005.
Please don't duplicate or re-publish this without asking first. Thanks.
