Monthly Archives: November 2008

The Drobo so far

With the Drobo up and running, I'm feeling a little safer. Right now, I have about 2 TB of disk space, which gives me just under 1 TB of available disk space. Of that space, I've used about half.

Overall, I'm very happy with the system. The largest drawback in this version of the Drobo is the USB 2. USB 2 is painfully slow compared to Firewire and SATA. However, in the way I'm using the system, the slow speed is tolerable.

The real test of the Drobo would be a hard drive failure. Sorry, I'm not going to even try to simulate that! Regardless, it will stay a part of the data protection plan for some time.

Another test of my backup strategy

It happened again! I had a hard drive crash. This time, the drive was a Seagate 1 TB drive about 60% full.

So what was my backup strategy and did it work?

I have three basic methods of backing up:

1. Time Machine – I use time machine to manage the backups of my laptop.
2. Backup to DVD – This method I was hoping to end. It's time consuming and hard to use with large groups of files. However, this has been relatively reliable.
3. Drive “mirroring” – Using tools such as rsync to maintain a second copy of a hard drive.

Method 3 is my latest approach and it's the system tested by my latest hard drive crash. Did it work?

Yes and no. I had a full copy of the drive where the data are safe. However, the backup itself was about 2 weeks old. As far as I can tell, however, about all I lost was a few downloads from the internet, including free iTunes songs and videos. So, I'd have to say the approach was reasonably successful.

One clear weakness of the approach was me. To make the system work, I have to do the mirroring far more frequently. Since I keep the mirrored drive offline when not backing up, this is not something I can do automatically (I have a LOT of data, so it's not practical for me to keep the drive online and active). So, I have to unmount another drive I'm using and add the mirror drive and then do the mirroring. This really can't change for me, so I need to make a regular schedule for now on.

The second weakness, which is far less obvious, is the lot of the hard drive. I worry that when I buy 2 hard drives of the same size and same brand, the drives come from the same manufacturing lot. Thus, if one is defective it's far more likely that the other is also defective (at least that's my fear). So, if one drive fails, as it just did for me, I worry that the other is also likely to fail putting my mirrored copy a high risk until I can get a replacement drive.

Given all these issues, I'm adding one more tier to my backup/data protection strategy. A Drobo. Drobo is essentially a low-maintenance RAID system (but not really a RAID). It holds up to 4 hard drives and allows you to mix and match drive sizes. If a drive fails, you pop it out and replace it. It is still likely to be vulnerable until replacement drives are installed, but the idea of not having to work about the timing of my mirroring would be a large improvement.

I've ordered a generation 1 drobo (since they're around $150 cheaper than the current model) from amazon and I'm already making plans to take advantage of the system.

However, this cannot replace the mirroring approach to backups. The Drobo will be used for more active projects and files, not long-term storage. Mirrored drives or DVDs will remain a part of my backup strategy for that work.

Right now, until I get the Drobo and replacement drives, I'm feeling vulnerable.