Backup and Recovery

Our recommended, comprehensive Backup and Recovery solution consists of:

• EMC® Retrospect® for Macintosh® Desktop Edition.
• A FireWire hard drive.

Why use Retrospect?

We use and recommend Retrospect Desktop Edition because it is the state-of-the-art in Mac backup and recovery. Retrospect can:

• duplicate any drive;
• perform incremental, scheduled, selective, or scripted backups;
• backup to any media (e.g. archive completed projects to CD or DVD);
• backup to server volumes;

and much more. Incremental backups, and the ability to archive to any media are worth the difference and the price for Retrospect when compared to other solutions.

Retrospect Desktop Edition also includes clients so you can backup up as many as three computers using a single license. Additional client licenses can be purchased. The clients included are for Mac, Windows, and Linux: if you have a heterogeneous environment at home or in a small office, you can backup more than just your Mac.

Retrospect's Immediate functions — including Backup, Duplicate, and Restore — are very easy to use. Retrospect also includes an excellent, detailed manual, as well as extensive Help, for all its advanced features.

When considering Backup and Recovery solution, you need to consider not just Backup but Recovery. Some solutions make it easy to Backup, but give little thought to a Recovery operation. We believe Retrospect has this covered better than any solution available. After all, the reason you implement a Backup and Recovery solution is for a comprehensive Backup and a painless, complete Recovery should disaster strike. Before you select a solution, look deeply into the Recovery side of things.

A free Trial Version can be downloaded from the link on this page. A variety of FireWire hard drives include Retrospect Express as bundled software. [1]

Why use a FireWire drive as your primary backup media?

We favor FireWire hard drives over optical media for regular backups, primarily for speed and convenience.

Regarding speed, backing up to, or restoring from, a FireWire hard drive is considerably faster than burning multiple CDs or DVDs, especially when large amounts of data are involved.

There are numerous reasons why a FireWire hard drive is more convenient that CDs or DVDs for regular backups:

• Backing up to a FireWire drive means not having to wait around to see if you will be asked to insert another CD or DVD, which can happen when backing up large volumes of data to optical discs. This also makes it very convenient to set up an automated backup procedure.
• You do not have to manage or store a variety of optical discs containing backups: everything is on the FireWire drive.
• Backups will neither be delayed nor incomplete due to having insufficient CDs or DVDs on hand.
• By partitioning a FireWire drive, one can maintain a variety of bootable Duplicates and Backup Sets of your system.
• In an emergency, one can simply grab the FireWire drive and go.

While one could still burn a regular backup to optical media for off-site storage, FireWire hard drives have become so inexpensive that having two such drives dedicated to backup is increasingly affordable. Alternating between a pair of FireWire drives — one to keep at home or the office, while the other is tucked away in a safe-deposit box — provides both on-site and off-site storage for backups in case of disaster.

Duplicates and Backup Sets

Two of the types of backups Retrospect enables you to create are Duplicates and Backup Sets.

A Duplicate is a bit-for-bit copy of a disk, partition, or collection of files. The data which has been backed up is saved to the Duplicate exactly as it was written on the disk from which it was copied. Think of a Duplicate as a genetic clone of the data that was backed-up.

Backup Sets are also exact copies of the data being backed up. However, the Backup Set saves the data which has been backed up in a special format used by Retrospect.

Duplicates are used to copy a disk, partition, or collection of files to another disk or partition of a size greater than or equal to the amount of data being backed-up.

The special format of Backup Sets enables you to save a variety of different backups on a single disk or partition. A Backup Set consists of one or two folders, depending on how much data has been backed-up. These folders contain the data which has been backed-up and a special catalog Retrospect creates for the Backup Set.

Because Duplicates are identical copies saved in the same structure as the original data, they have an additional special property: if you save a Duplicate of a bootable volume, such as your Mac OS X startup disk, to a dedicated partition, you can then start up or boot your Mac from the Duplicate. Since Backup Sets save the backed-up data in a special format, they are not bootable: if you backup your Mac OS X startup disk to a Backup Set, you have a complete copy of such, but that copy cannot be used as a startup disk.

Both Duplicates and Backup Sets can be updated incrementally for fast backups:

• When you first create a Duplicate, all of the data to be backed up is copied to the Duplicate. Subsequent backups to the same Duplicate can be defined so that only new or changed files are copied to the Duplicate, replacing older versions on the Duplicate. Likewise, files no longer on the source of the Duplicate, i.e. the disk or partition you are backing up, are removed from the Duplicate. In this way, the Duplicate is always an exact copy of the disk for which it is the backup at the time the incremental backup was performed.
• When you first create a Backup Set, all of the data to be backed up is copied to the Backup Set. The next time you backup the same disk, partition, or collection of files to that Backup Set, only those files which are either new or have changed since the last backup are added to the Backup Set. This means the second and subsequent backups to a given Backup Set — known as backup sessions — are performed quickly, depending upon the number of files that have changed. Since changed files are added, rather than replaced, you can restore an earlier version of a file which you have modified and backed-up in previous backup sessions.

As a general rule:

• Use a Duplicate, saved to a dedicated partition, to backup a bootable volume that one may want to use as a startup disk.
• Use Backup Sets to:
  • Backup volumes quickly and incrementally on a regular basis, saving both current and previous versions of changed files.
  • Backup multiple volumes to a single partition on your FireWire drive.
  • Backup Duplicates or when a dedicated partition is unavailable for a Duplicate of a given volume.

Partitioning a FireWire drive for Duplicates and Backup Sets

If you elect to employ a FireWire hard drive as your primary backup medium, per our recommendation above, you can partition the drive to save both bootable Duplicates and a collection of non-bootable Backup Sets. For example, depending on the disks being duplicated, a 250 GB FireWire drive (roughly 230 GB formatted) could be partitioned as follows:

Partition sizes for bootable Duplicates depend on the size of the spaced Used, as reported by Get Info, of the disk being duplicated.

The maximum partition size you would need for a Duplicate of a disk is the Capacity — as reported by Get Info — of the disk being duplicated. However, most of us are only using a fraction of the Capacity of the enormous hard disks in modern computers. Accordingly, it is not always necessary to size the partition that will contain a Duplicate equal to that of the disk being duplicated. When you Duplicate a disk, only the space occupied by data is duplicated: empty space is ignored. Hence one only needs to account for the space Used while including adequate room for reasonable growth.

As a general rule, we recommend the minimum size for a partition that will contain a bootable Duplicate to be 150-200 percent (1.5X - 2X) the size of the space Used — as reported by Get Info — of the disk being duplicated. If this computation results in a size larger than the Capacity of the disk being duplicated, then size the partition for the Duplicate to be equal to the Capacity of the disk being duplicated.

The following examples demonstrate these guidelines:

• Your Mac OS X startup disk is 60 GB in Capacity, but Get Info reports only 20 GB is Used. A bootable Duplicate of this disk would easily fit on a partition sized to 30-40 GB (1.5X to 2X the size of the space Used). This leaves considerable room for growth while maximizing the remaining free space on your FireWire drive for other partitions.
• Your Mac OS X startup disk is 60 GB in Capacity, and Get Info reports 35 GB used. Size a partition for a bootable Duplicate of this disk at 60 GB.

The remaining space on your FireWire drive, i.e. that not occupied by partitions reserved for bootable Duplicates, can be dedicated to a large partition for Backup Sets, or a combination of partitions for temporary storage and Backup Sets as illustrated in the table above.

Why you should implement this solution now

Unfortunately, too many folks fail to realize the value of a comprehensive backup and recovery solution until after disaster has struck. Of course, by then, it's too late. We believe that using a personal computer without a comprehensive backup and recovery solution is like driving without auto insurance.

Note: For step-by-step instructions on implementing the same backup and recovery solution employed by Dr. Smoke see the "Backup and Recovery" chapter in our book Troubleshooting Mac® OS X.

Notes

[1] The difference between Retrospect Desktop Edition and Retrospect Express (aka OEM Express) are that Retrospect Express lacks the following three features of Retrospect Desktop Edition:

• Two network clients licenses.
• Support for backup to tape drives.
• The ability to create custom Selectors.

An inexpensive option is available to upgrade Retrospect Express to Retrospect Desktop Edition.