Throttling ShadowProtect: FileSlinger™ Backup Reminder 02-15-08

PC Magazine raved about ShadowProtect Desktop 3.1. They called it “the fastest and smoothest backups and restores of any drive-image utility on the market,” so of course I went over to StorageCraft’s website and downloaded the demo.

The demo version doesn’t let you test ShadowProtect’s most interesting feature, “Hardware Independent Restore,” because that requires the StorageCraft Recovery Environment CD.

What’s Hardware Independent Restore? Only the Holy Grail of drive imaging: the ability to restore the image of one drive onto completely different hardware, or to a virtual machine. Most drive images, like the ones I make using Ghost 8, require identical hardware—and preferably the exact same machine you made the image from. Not just the same model of hard drive, mind you, but the same processor, monitor, optical drive, and what-have-you. Which is fine if you just had to replace a dead drive with an identical model, or if you want a quick reinstall, but not so good if your two-year-old computer just got destroyed in a fire.

The truth is, however, I’m not in a position to test Hardware Independent Restore, because I don’t have enough hardware. My secondary laptop has too small a drive to fit the image of my main laptop, and I’m not about to overwrite the main laptop’s drive just for the sake of testing a product. (Sallie, you have no confidence.) And though I am pretty geeky in my way, I don’t keep a spare test system. So I will either have to take StorageCraft (and PC Magazine) at their word about Hardware Independent Restore, or wait until the Ur-Guru can check it out on his multiple VMs.

So what about ShadowProtect’s other features? Once installed, the program presents you with a series of wizards and a fairly intuitive user interface. (At least, it seems to work and look a lot like other backup programs, and by comparison with Ghost 8, a preschooler could use it.)

One particularly cool thing about ShadowProtect is that it lets you include multiple drives in a single image. I have two internal hard drives on my main laptop, and other drive-imaging programs I’ve worked with can only back up one drive at a time.

For some reason, the first time I tried the Backup Wizard, it only showed me local drives as possible destinations for the backup. When I tried editing the backup job, I could find my network drive, but not connect to it. But I tried creating a new backup job just now and was able to connect to the network drive with no problem.

It was not quite as easy to make a successful backup as PC Mag’s review made out, though the first error was my own fault: since I couldn’t get to the network drive, I chose one of my external drives as the destination for the image, and it turned out I picked the one without any room left! (I need to go back through that drive and see what’s sucking up all the space in it, besides my Safety Drill backups.)

And the error message I came back to (I had set the program to run while I ate lunch) said “failed for unknown reason,” so I had to figure out what had gone wrong myself. (The User Guide says that the log files will give the exact reason, but I’m not sure anyone non-technical would even realize there was a log file, much less check it. I’m a geek manquee and I didn’t think to.)

So I started again with a new backup destination and headed off to my appointment. I got back several hours later to find the computer hibernating and another “backup failed” message. Puzzled, I tried again.

This time I noticed that the estimated time to completion was almost two days. That baffled me—especially given what the PC Mag reviewer said about fast backups. No wonder the backup failed, if the computer shut itself off for inactivity before it could finish! I canceled the backup and took a look at the advanced options to see what I might have missed.

The problem turns out to be something called “I/O throttling.” Neither the help file nor the user guide explains this terminology, but if I understand Wikipedia’s article on bandwidth throttling correctly, it means restricting the amount of data that can go out at any one time, in order to prevent “traffic jams.” (I/O, by the way, stands for Input/Output.)

In ShadowProtect, not only is I/O throttling turned on by default, but it’s set to 100%. As far as I can tell, what that means is that 100% of resources are devoted to moving any data besides what you’re trying to back up. Small surprise, then, if it was going to take more than a day to back up my C drive.

I set the throttle to 50% and got a much more reasonable backup time: 1 hour, 30 minutes, and 9 seconds at an average of 8.86 MB/second. And this time, the backup actually completed, and I could browse through it. Everything looked fine to me, but an attempt to verify the image failed—perhaps because verification is set to 100% throttle. (And I couldn’t find a control to turn it off, the way you can when making the image.)

On the basis of this very cursory examination (the program does a number of things I haven’t checked out), I would recommend ShadowProtect Desktop 3.1. But watch out for that throttle!