November 14, 2015

Data Loss

Someone once told me the problem with health insurance is you don’t know how good yours is until you need it, and by then it’s too late. The same can be said about computer backup recovery systems.

I’ve been using crash plan for two years now. Up until now I’ve been quite happy with our setup. My data is backed up in triplicate. One external hard drive drive (E:) contains all the raw images, directly off the camera, in the same directory structure the camera creates. Another drive (F:) has all my images organized, so I can easily find the photos I’m looking for. I’m using Crashplan to back up both those drives to another local hard drive (G:) and also to the cloud. More on the cloud later. I figured I had to be safe from data loss, right? How could three copies of my data not be sufficient?

I should mention that before creating the local backup instance on drive G:, I had tested the crash plan’s cloud backup. I say that as though the test was intentional, and not because I accidentally deleted a directory. Regardless, recovering the deleted files was easy peasy lemon squeezy so it never occurred to me to also test the local backup instance. That mistake is on me.

On October 17th my E: drive failed. All the light weight solutions – chkdsk, restarting, etc – where to no avail. My computer happily told me the disk was unreadable and suggested reformatting. I decided to not waste too much time trying to repair the drive. After all this was exactly the use case for the local crash plan backup. I reformated the drive and began the process of restoring over 296,224 files.

I got back 296,224 “Unknown problem” error responses.

At this point I wasn’t expecting to experience much, if any, data loss. I could still pay the $300 and recover from the cloud, and I had my F: drive which should be the same files. I say “should” because the two drives do get out of sink some times. I previously wrote a java program to run through the directories to warn me when this happens, but I couldn’t remember the last time I ran the job.

I couldn’t figure out what went wrong from the logs so I contacted tech support. Tech support theorized it was a known bug that affect NTFS file systems on Windows computer when the drive was reformatted. This was extremely frustrating to hear as NTFS is the default file system on windows, and recovering from a dead drive was, again, one of the primary uses cases for crashplan! Tech support’s suggestions included (1) try a different operating system, (2) reformat the drive to a different file system, and (3) downloand the files piecemeal. Of those, (2) was the least ridiculous. I reformatted the drive to ExFat and tried again.

I got back 411 files. A handful of iPhone photos and a bunch more “Unknown problem” error messages.

But this time I could tell there was still an error with the drive. The 2 TB drive was showing as full with just a handful of data. I reformatted again. Reformat failed. Repeat, repeat, repeat. After the fourth reformatting failed I purchased a new hard drive.

I got back 34k files.

The troubling thing now was crash plan was failing silently. There was no error given. The only indication that something had gone wrong was the fact that I had only gotten back a tenth of my files. I tried again, more silent failures. At this point my confidence that I was going to get back all my data was waning so I started looking into the cloud.

I had two options when it came to restoring from the cloud. The first was to download all 2TBs worth of data in 500 MB chunks – 4000 chunks to be exact! The second was to pay $300 to “Restore to Door”. I had originally thought “Restore to door” meant they send you a hard drive with all your files in tact. Nope, they send you a local crash plan instance you can restore from. Basically I would have another copy of my G: drive. That didn’t leave me much hope that it would fair any better.

I restored again, this time a smaller subset of photos from my local backup. Success! Restored again, more success! I was able to partition my data into five chunks and restore each chunk without issue. The process took two weeks, as I kept getting stuck waiting for crashplan maintenance modes; deep pruning, synchronizing, etc. The deep prune itself took four days to complete.

In the end I lost just 16 photos. I’m not happy about that, but I can live with it.

My lessons learned:

I’m not the typical use case Crash Plan was designed for. Crashplan is sort of a light weight version control system in addition to backup engine. It keeps multiple versions of your files (as many as you specify), and are constantly scanning your file system looking for recent changes. In doing so they make the design decision to focus on recently changed files. That makes a lot of sense if your backing up your working directory. You probably want/need the latest version of any paper your writing, or program your coding. It makes less sense if you’re backing up an archive full of photos. I want at least one version of every photo backed up. I can always re-edit them, but I can’t re-shoot them!

I have more data than the typical Crash Plan user. When I was searching through the forums looking for tips on how to speed the process up, (4 days to deep prune, are you kidding me?!), I found a number of folks with similar problems, each with large data sets. Between all our home computers we had backed up 3TBs worth of data. I had already busted the memory of the app as high as their sample recommendations go, and went even higher during this process. I’m starting to reach the point where crashplan just cannot hold everything in memory it needs to. When that happens with any program performance drops off a cliff. When crash plan runs there’s not a lot else I can do with the computer.

The Verdict on Crashplan:

Obviously the continuing to fail drive was not Crashplan’s fault, and I was able to recover almost all of my files. Still, taking two weeks to recover a hard drive seems a bit excessive. I take a lot photos, and I don’t expect that to change any time soon. Crashplan just may not be right for my use case. I have a little over a year left on my crashplan subscription and I see no reason to jump ship now. I may look into alternative back up options when the end of the subscription nears.

Related posts:

Posted in Internet & Technology | Tags: ,


Comments

Trackbacks

  1. […] style that I use for Alexis’ first year scrapbook. Then my hard drive crashed, and in the ensuing chaos I wasn’t much in the mood, nor had the time to pick up my camera. At the start of November, […]


Leave a Reply

Your email address will not be published.