Tech Life of Recht

On Thursday, I was downloading some files and preparing a Spring course for work when suddenly my disk was remounted read-only, with some pretty scary messages in the syslog. What exactly went wrong is unknown, but the filesystem was pretty much gone.

I did a raw disk backup using

dd if=/dev/sda

Then I booted a rescue cd (I just used an Ubuntu 9.04 installation cd) and ran fsck -n /dev/sda3, just to see if fsck could make it through. It turned out it couldn’t, it failed with a message like

“error while iterating over blocks in inode , aborting”

And then fsck would stop. Of course, the filesystem couldn’t mount, and I didn’t have a recent backup, so I was somewhat screwed.

Google didn’t help much, other than the usual advice to format (or buy a new disk) and reinstall, which was not exactly an option. So I fired up debugfs and dug around a little. At this point, I just wanted to salvage as much as possible, and I was quite aware that some dataloss was inevitable.

The magic commands in debugfs turned out to be
clri
freei
kill_file

Running these 3 commands every time fsck failed got fsck all the way through the repair process. At some point, fsck began complaining about corrupted directories, but the same 3 debugfs commands also took care of this.
I was then able to mount the disk and copy all files to an external device. Of course, the most important dir, my home dir, was gone, and lost+found contained a couple of thousand files and dirs, which I have now gone through to find most of the important stuff I had on the disk. Now I just need to get a new disk, reinstall and copy as much as I can from the old disk.

One week in San Francisco is over, and I’m slightly jetlagged. However, it was a nice little trip, and the Google I/O conference was actually pretty good. I’d feared that it would turn out to be a complete fanboy conference, but luckily it wasn’t that bad, and most of the talks I went to were of pretty high quality. I mostly went to the GWT talks about the upcoming features in 2.0, and how to structure large GWT applications.
As most people know by now, the conference wasn’t entirely without hype. First, there was the Google Android phone giveaway, which I must admit was pretty sweet. I’d thought about buying an Andriod-based phone, so getting a free one couldn’t be any better – especially because it came with a 1 month subscription and in unlocked condition. I’m still getting used to the phone, but I like it more than my iPhone – probably mostly because I’m not tied in to the 2nd evil empire.

The second hype-event was the Google Wave presentation. Also some pretty sweet stuff, especially considering that it was all a web application based on GWT. Time will tell if Google Wave will live up to the quite large amount of applause given at the presentation, but it seems like it has the potential to have quite an impact. I’m certainly looking forward to getting access to the sandbox environment, and even more to getting a look at the source code when it becomes available.

The conference was only two days, so there was time for some sightseeing and shopping. Just in case anybody else doesn’t know it: Playstation 3 games for region 1 (USA) can be played on a region 2 device (EU). Oh, and if you rent a convertible, you should probably consider putting on some sunlotion before driving around the entire day with the roof off.