Dear Fellow System Administrators, I like excitement in my life. I go on roller coasters, I ride my bike without a helmet, I make risky financial decisions. I...
Dear Fellow System Administrators, I like excitement in my life. I go on roller coasters, I ride my bike without a helmet, I make risky financial decisions. I treat my servers no differently. When my Linux vendor releases security updates, I think: I could apply these patches, but why would I? If I did, I'd have to coordinate with my users to schedule a maintenance window for 2am on a Sunday and babysit those systems while they reboot, which is seriously annoying, hurts our...
Dear Fellow System Administrators, I like excitement in my life. I go on roller coasters, I ride my bike without a helmet, I make risky financial decisions. I treat my servers no differently. When...
It's a well-documented fact that RAM in modern computers is susceptible to occasional random bit flips due to various sources of noise, most commonly...
It's a well-documented fact that RAM in modern computers is susceptible to occasional random bit flips due to various sources of noise, most commonly high-energy cosmic rays. By some estimates, you can even expect error rates as high as one error per 4GB of RAM per day! Many servers these days have ECC RAM, which uses extra bits to store error-correcting codes that let them correct most bit errors, but ECC RAM is still fairly rare in desktops, and unheard-of in laptops. For...
It's a well-documented fact that RAM in modern computers is susceptible to occasional random bit flips due to various sources of noise, most commonly high-energy cosmic rays. By some estimates, you...
About nine months ago, I lost a lot of free time to a little applet called Pentris. The addition of pentomino pieces made the gameplay quite different from the...
About nine months ago, I lost a lot of free time to a little applet called Pentris. The addition of pentomino pieces made the gameplay quite different from the original falling block game, but I couldn't help but think that Pentris didn't go far enough. As a programmer, I had to implement the natural generalization of the game. After a much longer development cycle than I had originally anticipated, ntris is now ready. (You'll need Java to run the applet.) In ntris, as your...
About nine months ago, I lost a lot of free time to a little applet called Pentris. The addition of pentomino pieces made the gameplay quite different from the original falling block game, but...
I'm not a big sports aficionado. However, I'm compelled by virtue of living in Boston to care about baseball, and I just finished reading Moneyball, which is...
I'm not a big sports aficionado. However, I'm compelled by virtue of living in Boston to care about baseball, and I just finished reading Moneyball, which is all about baseball statistics. One thing about baseball I definitely appreciate is that there are lots of published statistics, because lots of statistics means nice big public data sets available for my relational database querying pleasure. Let's use baseball statistics as an excuse to learn more about query planners...
I'm not a big sports aficionado. However, I'm compelled by virtue of living in Boston to care about baseball, and I just finished reading Moneyball, which is all about baseball statistics. One thing...
I'm a recovering perl hacker. Perl used to be far and away my language of choice, but these days I'm more likely to write new code in Python, largely because...
I'm a recovering perl hacker. Perl used to be far and away my language of choice, but these days I'm more likely to write new code in Python, largely because far more of my friends and coworkers are comfortable with it. I'll never give up perl for quick one-liners on the command-line or in one-off scripts for munging text, though. Anything that lasts long enough to make it into git somewhere usually gets rewritten in Python, but nothing beats perl for interactive messing with...
I'm a recovering perl hacker. Perl used to be far and away my language of choice, but these days I'm more likely to write new code in Python, largely because far more of my friends and coworkers are...
Wireless traffic is both interesting and delightfully accessible thanks to the broadcast nature of 802.11. I have spent many a lazy weekend afternoon watching...
Wireless traffic is both interesting and delightfully accessible thanks to the broadcast nature of 802.11. I have spent many a lazy weekend afternoon watching my laptop, the Tivo, and the router chatting away in a Wireshark window. As fun as the wireless traffic in one's house may be, there's something to be said for being able to observe a much larger ecosystem - one with more people with a more diverse set of operating systems, browsers, and intentions as they work on their...
Wireless traffic is both interesting and delightfully accessible thanks to the broadcast nature of 802.11. I have spent many a lazy weekend afternoon watching my laptop, the Tivo, and the...
There are many different kinds of bugs with many different causes. Sometimes, it's just some silly typo or type mismatch; other times, it's an algorithmic issue...
There are many different kinds of bugs with many different causes. Sometimes, it's just some silly typo or type mismatch; other times, it's an algorithmic issue or a correctness error; and occasionally, it appears to be something much stranger. This is a story about that last kind of bug, where finding the location of the problem is relatively straightforward, but figuring out how to fix it, or even why it's happening, isn't so easy. We first meet our hero, yours truly, as he...
There are many different kinds of bugs with many different causes. Sometimes, it's just some silly typo or type mismatch; other times, it's an algorithmic issue or a correctness error; and...
If you're a veteran system administrator, you might remember an era of extremely expensive hard disk storage, when any serious network would have a beefy...
If you're a veteran system administrator, you might remember an era of extremely expensive hard disk storage, when any serious network would have a beefy central file server (probably accessed using the Network File System, NFS) that formed the lifeblood of its operations. It was a well-loved feature as early as Linux kernel 2.0 that you could actually boot your machine with a root filesystem in NFS and have no local disk at all. Hardware costs went down, similar machines...
If you're a veteran system administrator, you might remember an era of extremely expensive hard disk storage, when any serious network would have a beefy central file server (probably accessed using...
~jesstess
