lunatech's immutable laws of life

rshekhar@rshekhar$ dict hypothesis 
From WordNet (r) 2.0 [wn]:
  hypothesis
       n 1: a proposal intended to explain certain facts or observations
       2: a tentative theory about the natural world; a concept that
          is not yet verified but that if true would explain certain
          facts or phenomena; "a scientific hypothesis that survives
          experimental testing becomes a scientific theory"; "he
          proposed a fresh theory of alkalis that later was accepted
          in chemical practices" [syn: {possibility}, {theory}]

Here are some of my hypotheses, tentatively named lunatech's immutable laws of life

  1. All new PHP programmers want to write a content management system
  2. All new Java programmers will write a chat client
  3. All college students love complexity and will do everything to increase it (at least the amount of complexity in their lives)
  4. All college students want to do a project in 'networking'

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bayesian filters

Some weeks back, I was talking with my manager about AI and how it is such a bogus field. My manager replied that in a few years we will see applications that use AI in our daily life. However, I was quite skeptical - and I refused to agree to this. He then gave an overview of neural net and how they can learn to solve the problems. Here I pointed out that Bayesian filters can also be considered a form of AI, as they can learn from their previous data and they can make decisions, but Bayesian filtering is mathematics and not AI. At this he replied that most of AI is mathematics and only some part of it is hocus-pocus and hand waving.

This brings me what I have been thinking for a long time.Joel write

A very senior Microsoft developer who moved to Google told me that Google works and thinks at a higher level of abstraction than Microsoft. "Google uses Bayesian filtering the way Microsoft uses the if statement," he said.
. I had always suspected this and had also felt that this was the way to go. A few months back, we had a presentation by a researcher (not a Yahoo! employee), who was working on extraction and summarization of documents. He had a formula that he was applying on the sentences of the documents to find the weight of the whole sentence and then finally if the weight of the sentence was above some limit, it showed up in the summary. I was skeptical about this approach - my belief is that the Bayesian approach can be used to classify documents. Luckily, there is a project that seems to provide a framework on which things can be built further.

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Moving the MySQL's datadir directory.

By default, MySQL's datadir is placed in the /var/lib/mysql directory. However, if you are planning on using MySQL tables to store a lot of data and your /var partition is small, it might cause you problem at a later stage. In such a scenario, it is better to move the MySQL's datadir to another partition (like /home.

The steps are

  1. Stop your mysql server before starting this operation
  2. Create the directories that will be new datadir
  3. chown the directory to the mysql:mysql user
  4. copy the files from the old datadir to the new location. However, make sure that the files named ib_arch_log_0000000000, ib_logfile0 etc. are not copied to the newer location.
  5. Make sure that the files and directories are owned by mysql user
  6. Make changes in the my.cnf to point the new datadir.
  7. Restart the MySQL database
  8. You might need to do varying degree of troubleshooting to get the server working if there is some problem
  9. Create a new database and verify that the files for this database are getting created in the new datadir
  10. After the server is running for a few days properly, get rid of the old data.
  11. Sleep
I tested these steps on MySQL 4.0.24 and all my tables were MyISAM type.

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ingenious social enginering to know when your network traffic is being watched

from Tao of security blog, I came across this

One of the details that emerged from Curt's monitoring of the Invita Security network involved a password used by Alexey Ivanov. When accessing one of his drop sites, Alexey's FTP password was www.pidor.com (Internet Archive available). Think of what an unwary analyst might do with that information. Only someone who is monitoring Alexey's actions might know about www.pidor.com. Say that unwary analyst decides to visit www.pidor.com to learn more about the site. If Alexey or a friend is monitoring Web accesses to www.pidor.com, they could learn that they are being monitored. This case demonstrates how important it is for analysts to not "touch" remote or foreign sites involved in intrusions. You may tip your hand to the attacker and ruin an investigation or recovery effort.

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