Everyone has a mission-critical application -- that one program they can't work without (Adobe Photoshop, Microsoft Excel, or Apple's Final Cut Pro, for example). But backup programs are mission critical for all users, no matter how they earn a living. Dantz Development's Retrospect backup software, the most popular of this genre, performs full and incremental backups of local and networked Macs and saves data to a wide variety of storage devices.

Many people waited to upgrade to Mac OS X until Retrospect 5.0 (   ; July 2002) was available for the platform. And many people have also held off on upgrading their servers to Mac OS X 10.3 (Panther), due to its incompatibilities with Retrospect 5.1. Retrospect 6.0 addresses those incompatibilities but otherwise offers only a few new features, which are aimed at people using Retrospect to back up very large amounts of data.

New Features

The main change in Retrospect that's likely to get non-enterprise users to upgrade is Panther compatibility. Panther introduced FileVault and Fast User Switching (among other things), and Panther Server introduced case-sensitive HFS+ (in which documents named thisfile and ThisFile can exist in the same folder). These changes caused trouble in Retrospect 5.1, forcing careful users to either work around the problems or hold off on upgrading the Macs running Retrospect to Panther, though client Macs could be upgraded individually without ill effects.

Panther Issues

In our testing, Retrospect 6.0 successfully worked around such obvious issues with Panther by adding an option to ignore FileVault-sparse images (a disk image of your entire Home folder that, when any small change occurs, must be backed up in its entirety, adding many gigabytes to your backup set every day) and refusing to allow multiple users on the same Mac to launch Retrospect simultaneously. These changes make it possible to upgrade any Mac running Retrospect to Panther.

Retrospect's most compelling new feature is its improved backup to hard drives, which are now the most cost-effective backup media for small to medium-size networks, thanks to low prices and ever-increasing capacities. Retrospect 6.0 significantly improves backup performance to external FireWire drives.

Another major change, however, is support for backup sets that span multiple hard drives as though they were tapes or optical discs. This allows a hard-drive–based backup set to grow indefinitely, something that wasn't possible before. In Retrospect 5.1, a backup set was limited to the size of the drive, which forced manual intervention in the form of eras-ing the backup disk and starting over, or starting a whole new backup set when a drive filled up. This change makes hot-swappable FireWire drive bays such as Granite Digital's FireVue (   ; Reviews in Brief, January 2004) and WiebeTech's BayDock (866/744-8722, www.wiebetech.com) particularly attractive backup devices, since you can now back up to a series of inexpensive hard-drive mechanisms installed in hot-swappable trays.

Enterprise Benefits

Enterprise users will appreciate Retrospect's other new features, though they may be left wanting more. The program now supports the Xserve RAID, as well as SCSI and Fibre Channel tape-drive libraries, with features such as bar-code inventory (which allows the program to quickly locate and identify tapes) and more than 128 tape slots. Users running OS X 10.3.3 with a tape autoloader or Fibre Channel library must download Retrospect's free upgrade (to version 6.0.193), which enables these drives to work again. A change in 10.3.3 had rendered such drives inoperable with Retrospect 6.0. In addition, Retrospect's backup sets can grow beyond the previous limit of 1 terabyte, a necessity for organizations with massive quantities of data generated by video, genomics, or other data-intensive fields. For people who have bumped up against Retrospect 5.1's backup-set size limits or been forced to jury-rig a backup strategy for lack of appropriate device support, Retrospect 6.0 is worth considering.

Not Looking Back

Although Retrospect 6.0 can read and restore backup sets created by previous versions, the addition of Unicode and terabyte support forced a change in the backup-set format such that users must reset existing backup sets or create new ones, an annoying requirement for companies with complex backup procedures. The Retrospect 6.0.193 update enables new media backups to backup sets created by previous versions. This is a welcome change that lets companies add to existing backup sets without erasing old media, an act that could be troubling for legal or auditing reasons.

All Must Upgrade

The lack of backward compatibility extends to Retrospect clients as well; all copies of Retrospect Client on networked OS X Macs must be upgraded to version 6.0. Although Retrospect 6.0 can update all connected clients and is smart about updating only those that need it, ensuring that every Mac on a large network is updated is onerous. It would help if Retrospect could use OS X's Wake For Ethernet Network Administrator Access feature to wake sleeping Macs for backup or client update.

Administrators of networks large and small must still initiate file restores for users who have lost data, since the Retrospect Client software running on each networked Mac doesn't let individual users restore their own files. Such a feature would potentially reduce the load on network administrators. Lastly, unlike the Windows version of Retrospect, which can run multiple simultaneous executions, Retrospect for the Mac is still limited to a single execution at a time. Multiple simultaneous executions improve overall backup speed and administrator productivity, in part, because one slow client can't make every other client computer wait to be backed up.

Macworld's Buying Advice

On the surface, Retrospect 6.0 is a fairly minor upgrade offering compatibility changes and a few new features. Users who want to run Retrospect on their desktop Macs with Panther should definitely upgrade to version 6.0. But for people who see no reason to upgrade their servers from Jaguar, the other changes in Retrospect 6.0 may not warrant paying for an upgrade right now. But large companies with significant backup needs, and people looking to move up to backup software with network and large media support, should upgrade to version 6.0.