Author Archives: ward

grub rescue commands

I wasted some time on Friday trying to get a machine with grub 2 installed to boot. The machine booted into Grub’s rescue mode. Grub 2′s rescue mode is nice, but not exactly intuitive (no ‘help’ or ‘?’ command), and … Continue reading

Posted in Sysadmin | 1 Comment

disk, disk, disk

I started adding 165 TB of disk to one of our clusters today. This is what that looks like – 55 three TB disks: The packaging was not too great; while all disks were well packaged individually, the big boxes … Continue reading

Posted in Hardware, Sysadmin | Leave a comment

idle power draw of modern Opteron CPUs

I’ve been curious for a while about how much power Opteron CPUs draw when idle, so I set aside a bit of time to do some measurements. I used a Supermicro 1U system with redundant power supply. The motherboard model … Continue reading

Posted in Environment, Sysadmin | 3 Comments

acts_as_paranoid and acts_as_versioned on Rails 3

A few years ago, I described how to combine acts_as_paranoid and acts_as_versioned in order to make deleted records end up in your versioning tables. In order to do the same thing under Rails 3, I had to make a few … Continue reading

Posted in Rails | 1 Comment

compression

Before: -rw-r–r– 1 root root 1.1G 2010-10-31 20:19 10125-127-2010-10.error After: -rw-r–r– 1 root root 11M 2010-10-31 20:19 10125-127-2010-10.error.bz2 Bzip2 reduced the file to 1% of its original size. Not bad!

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resistor captcha

Adafruit Industries uses an awesome captcha. For an example, look at the Kinect bounty page (scroll all the way to the bottom).

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64K hours

Some disks last a long time. This is an old IBM IDE drive (IC35L040AVVA07-0). smartctl version 5.38 [i686-pc-linux-gnu] Copyright (C) 2002-8 Bruce Allen Home page is http://smartmontools.sourceforge.net/ === START OF READ SMART DATA SECTION === SMART Self-test log structure revision … Continue reading

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microsoft discovers remote attestation

Via slashdot: Microsoft’s corporate VP for trustworthy computing – Scott Charney – has published a position paper that boils down to remote attestation: let ISPs cut off internet access for computers that are not deemed free of malware. So… how … Continue reading

Posted in Free Software/Open Source, Hardware | Leave a comment

Intel selling crippled CPUs

Via boingboing.net: Intel is now selling crippled CPUs that can be ‘upgraded’ through the purchase of scratch cards (!) with a code. That code can be entered in the BIOS of the computer, thus unlocking additional horsepower. I’m running out … Continue reading

Posted in DRM, Hardware | Leave a comment

View from my ‘office’

Sadly, this is just for a few weeks…

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