The Joy of Backup

A couple days ago, I discovered that my hard disk was failing.  I decided that the best COA was to do nothing about it except posting on my blog.  The reason is that I’ve been using Time Capsule and Time Machine for hourly backups for very long (since the beginning of September 2009, where I upgraded to Snow Leopard and archived my old backup), so I was not nervous about losing any data (my most recent backup was only 10 minutes old).

So, yesterday I decided to reboot my computer and test out the hard disk using the installation media.  This did… Something.  Anyway, I was not able to boot my computer afterwards.  I did not really want to spend any time figuring out what the problem was, so I decided to just say screw it and reestablish my backup.

Only problem was that I have a bunch virtual machines, 50 GiB worth of them, I didn’t have recent backups off (generational backups take too much space for those).  Luckily, I has spare room on my server and could just copy them over.  If I could mount it (I could not boot the computer).  Luckily, the installation media had already booted my old installation and allowed me to escape to a command prompt, and after issuing a

mkdir /Volumes/Users
mount_afp afp://michael:<password>@coherent/Users /Volume/Users

I could back up all virtual machines using

cp -Rv /Volumes/morphism/Users/michael/Library/Parallels /Volume/Users/Shared/Dropbox

This of course, took a quite a while (though, backup is not too bad when it happens at 1750 MiB/minute).  It is also possible to see the backup in my server stats for the last couple days.  The two big spikes are backup and restore, the small spikes before the big spike is the hourly backup of my server and the silence between is me disabling backup while restoring the operating system onto my desktop.

After that, I decide to zero out the hard disk (write 0 over all old data).  This exercises the disk and locates any bad sectors, hopefully prolonging the life.  It does not, however solve the problem.  It only allows me to use the hard disk without fear that too much data is lost.  Because I have a backup and can restore to any point in time in the last 6 months.  Otherwise, this is a big no-no and will corrupt your data.

Also, it seems my drive really is failing big time, to the point I will need a new one and soon:

2 thoughts on “The Joy of Backup

  1. Just a little curious: Why do you hide Drive Model and Serial Number? Not that it matters to me, but does it matter to anyone?

  2. In my opinion it is always better to hide such identifying information. The drive model is most likely overkill, but the serial number is unique and used for tracking stolen goods, and publishing that only could potentially allow people with a grudge to report this number as stolen.

    For a hard disk this is less important but for a computer, there are actually web-sites tracking and reporting this information. This can make it difficult to sell off the shebang afterwards:

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