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Saturday 22 November 2008
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From TNPC issue #4.18...
Retrospect: Is This a Better Backup?by Al GordonSeptember 6, 2001 Dantz Development wants to establish a new paradigm for backup software with its Retrospect lineup. (Hey, gimmie a break--I have been trying to work "paradigm" into an article for five years.) The premise of most backup programs is disaster prevention: a hard drive fails, a virus wipes out data, or you erase the Jones project files only to discover that you still need them. The emphasis generally is on enabling the user to get back the latest and greatest version of any missing file when that file has been corrupted or erased. Retrospect, just out in version 5.5, focuses instead on taking
"snapshots" of the state of your system at the time a particular
backup ran ($45.99 on CD-ROM): This marries backup with the "rollback" concept built into
Windows ME and XP and in Roxio GoBack Deluxe 3.0 ($39.99): The idea is that the ordinary changes in today's networked and Internet-connected PCs, as well the system changes made by software installs, can and do mess up your system much more frequently than disasters. Retrospect allows you to say, "OK, my system was working on Tuesday, I want to set it back to the way it was then," and then lets you go ahead and do just that. A conventional backup program such as Veritas Backup Exec Desktop
Pro (see link below to my article in #3.23) relies on your
operating system's "archive" attribute--an electronic marker that
should be associated with new or changed files on your system.
When you do a full backup, Backup Exec will turn off the archive
flag on all files. Subsequent partial backups then look for files
which have the attribute turned on. The full backup is the key
process, and interim backups are based on it. Further, the
restore process is designed to put back all files that were in
the full backup or were added subsequently. Retrospect, on the other hand, monitors files through an elaborate catalog database that determines whether a file is new or modified. The criteria are proprietary, but if you right-click on a file in Windows Explorer and look at "Properties," it is clear that the file system keeps a substantial amount of data that could be tracked. With files monitored that way, there is no need to do as many full backups, as the software can more effectively manage interim backups. More important, the cataloging makes restores more precise, pinpointing the files-- and system state information--that were on your PC at any particular snapshot point. (Snapshots are taken every time Retrospect does a backup, be it full or partial.) Retrospect's restore options allow you to make certain that you don't overwrite your latest data. Specifically, suppose you do a full backup every Sunday and partial backups the rest of the week. Let's say that on Tuesday you added some file to your system, which remained on your system for Tuesday's backup but which you then erased on Wednesday. If you then need to use Retrospect to restore your system to Monday's state, Retrospect will not put that Tuesday file back on your PC whereas conventional backups would. At a minimum, this means that restores don't clutter your hard drive with things you had discarded. If the discarded file happens to be the cause of your system problems, it means that the restore won't undo your fixes. Eric Ullman, Dantz's tireless technical market chief, suggests that users will find it a major time-saver to use a debug-then- rollback rule similar to those many corporate IT departments employ with Retrospect: If your computer starts acting up, instead of spending several hours trying to figure out what's ailing it, try a couple of obvious fixes and if they don't work, use Retrospect to roll your system back to the last time it was working correctly. Because Retrospect keeps the number of files to be saved or restored to a minimum, the operations are faster and your system is tied up less. As a result Retrospect was the first backup program I was willing to entrust with automated backups on my system as the backup could run without putting me out of action for an inordinate amount of time. I also like the wide range of options it allows you to set for backups. You can filter in or out files according to very flexible criteria. Want to do a backup of just your Word documents and templates? Set Retrospect to backup "*.do?". The scripting for automatic processes is easy once you get used to it, and there are all manner of utilities for managing your backup media. My guess is that many TNPC readers probably will like Retrospect. But... yes, there always is a "but," it is not for everyone. Retrospect's original strongholds were the Macintosh and Server markets, and the interface shows it. You need a sense of experimentation, if not adventure, and a great deal of patience to figure out how to do things. To play in the Windows Desktop space, Dantz needs a major interface overhaul, including the use of standard Windows Explorer navigation dialogs, more wizards, and improvements to a really awful help file. To cite an egregious example, the major new feature in Retrospect 5.5 was the addition of a disaster recovery utility. This, however, is not addressed in the help files, you have to find the instructions in a readme document. Similarly, Dantz uses "recycle backup" as its term in automating backups to mean a backup that erases an existing tape or other media, and records the new backup on the old media. (This is the equivalent of the overwrite command in Backup Exec Desktop.) But you cannot find the definition of "recycle backup" in the help files. Retrospect 5.5's approach to disaster recovery, in fact, is kind of a metaphor for the software's strengths and weaknesses. Dantz took a novel approach by creating a "disaster recovery preparation wizard" that creates an "image file" that CD burning software can then use to make a bootable CD. That CD, along with your backup media, and your OS setup disk provides the necessary information to restore a crashed drive. But to use it, you do have to have a system that supports bootable CDs, and an understanding of how to set your system BIOS to run them. Some users will see that as a little too awkward. Backup Exec Desktop is still the product of choice for those who like "easy." With each evolution, however, Retrospect is getting more accessible. And its combination of rollback capability with backup provides a valuable defense against exactly the kind of computer woes we most often face. POSTSCRIPT: After I had finished writing this review, I abruptly found myself in the middle of a real-life system crisis rather than a test scenario. A simple uninstall/re-install project had gone wrong and Windows 2000 was blue screening when I started up the PC. As a believer in dual-booting, I had a second OS available to me, and that did boot up--establishing that the problem was software not hardware. I ran Retrospect from the second instance of Windows, and set up a restore to overwrite the partition containing the corrupt system. Retrospect analyzed the partition, identified the files it needed to replace (only about one-third), and made the repairs. I restarted the PC, chose the troubled instance of Windows 2000, and I was back up and running. Since this was a particularly crucial partition containing the files that boot the computer into Windows 2000 as well as Windows 2000 OS files themselves, this was an especially crucial test. And Retrospect did the job. You can reach Al Gordon at:
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