View Full Version : Sparse Image Reliability?

08-17-2008, 04:49 PM
Until now I've been avoiding using sparse images for just about everything, including SuperDuper backups. I do this because it seems like I'm constantly reading about images getting corrupted and losing their entire contents. It's not just here, I seem to run across these stories all over the place. Not the kind of thing I want to rely on for my backups.

Well, now I'm wanting to do some backups over my LAN to a remote server and the only method SD supports is writing to an image on a network mounted volume. The backups will go onto some external firewire drives, but I want them to be located in another room with my server rather than in my den. These are not boot drive backups BTW.

I'd like to hear what the collective experience is using sparse images with ongoing Smart Updates. Have they been reliable for you? Have you had any corruption issues? I'm really hesitant to pull the trigger on using them for fear of reliability issues. I think the read-only dmg images would be reliable, but obviously I don't want to do a full backup each time. I'm more concerned about the sparse images getting corrupt over time as Smart Updates continually expand and contract them.

What has your experience with sparse images and Smart Updates been?

08-17-2008, 05:25 PM
My general feeling is that they're fine for a secondary backup (and I use them that way myself). But I always maintain a primary backup directly to the drive.

It's not so much 'expanding and contracting' that causes issues: it's the simple fact that you're putting all your 'eggs' in a single, large file that acts as a virtual drive. If that file gets damaged, it tends to hurt the whole thing, rather than just having, say, one unreadable file.

08-17-2008, 06:41 PM
Dave - Thanks for asking this question!

Dave - Thanks for answering it. I've been wondering about this myself for a long time.


Dave (too many Daves)