Yesterday I did a very interesting discovery. Mozy backup was finished and the status screen mentioned that about 30GB had been backed up.

Wait a minute… only 30GB?!? I was expecting about 330GB!

So I started my investigation.

I have a Mac Mini with Snow Leopard. I am not sure about what version I am using. I assume the most current version . According to the log file the version is: 1.6.0.48085.

When I opened ” Mozy home”  and checked the history I noticed something weird: at a specific moment in time (about a week ago) the backup size was reduced by 300GB! This occurred after a message indicating that the backup had not finished.

Hmmm, then I went online. I logged on to the Mozy website. There I went to the restore screen. When selecting ” all dates” all backup data was visible as expected. However, when I selected the current date, i.e. 26 January, some folders were missing. Also the size of the online backup set was greatly reduced. Please see the images below.

The missing folders are my pictures that are stored on an external drive. I do a local network backup of these files, but as a secondary backup I use Mozy as well. If for example my house would burn down I would have still have a backup.

So the files on my external drive were not considered to be part of the current backup set anymore. Well, that is according to the site. Then I went to check the configuration in Mozy home. Then I was totally flabbergasted: in the client the folders on my external drive were marked for backup. The icon used was actually green. As a simple user I would consider this to be ok. Fortunately I was very eager to get to the bottom of this.

I decided to contact support. On the site there is a link to chat with support from Mozy. This is a feature that I have never used on a website before. Within seconds I was explaining the problem. The support engineer checked my account and listened to my explanation. His suggestion was to open Mozy home and to empty and mark the checkbox for this folder again. His diagnosis was that somehow my external drive must have been disconnected during one of the backup operations. I know that my external drive is always connected when my Mac is on. But of course something might have gone wrong one day.

So, I did what he suggested. It started backing up all the files again. Well, “relinking” the files actually. Since the files were still available online they were not actually transferred again. If this error would have occurred more than 30 days ago I would have had to spend several weeks backing up my files again.

This morning there was a mail from the support guy asking whether my situation was resolved. I indicated that the backup was at 80% and that his suggestion seemed to work. I also indicated that I think that this behavior is a very serious error in this kind of application. The backup software is used as a sort of insurance. Fire and forget. Unfortunately it should be monitored very carefully to prevent data loss since the software is not resilient enough to deal with this.

I would expect at least a very, very, very clear error message indicating what happened and what it means for my backed up files! Or even better, the software should be able to deal with external drives, USB sticks, etc. even if they are not always present in the system. If they are not present it does not mean the files have been deleted and as such can be removed from the online backup set.

So I did a feature request/suggestion. Let’s see how it works out.

My current opinion about Mozy:

• Service: ++
• Reliability of Windows client: +
• Reliability of Mac client: +/-