How to Speedup Linux Boot Process using Startpar Command Examples

by Karthikeyan Sadhasivam on September 10, 2014

In a typical scenario, during the boot process, the run-level system startup scripts are executed one-by-one.

A particular run level startup script will not execute until the previous script is executed completely. If a particular service during the startup is hanging for some reason, it might take a while before it times-out and move on to the next startup script.

Startpar utility is used to run multiple run-level scripts in parallel. This helps to speed up the boot process of your server.
(more…)

To understand fuzzy logic, let us take a very simple example.

Imagine a simple light bulb which has two states: light on and light off.

We can mark the light off as false, and light on as true. This would be simple system that has two states and is described with George Boole’s logic. In his honor we have bool data type in C++.

Next, imagine that the simple light bulb could also be dimmed.
(more…)

In the past few articles in the Python series, we’ve learned a lot about working with regular expressions in Python.

In this article, we’ll explain how we could use python regular expressions for a realistic task.

We’ll do a step by step walk through on how we can build Python data structures from formatted flat text files.
(more…)

How to Add Multiple Routes in Linux Using ip Command Examples

by Karthikeyan Sadhasivam on August 21, 2014

Apart from the default route, you can also configure additional routes.

For example, your server you might have 2 interfaces (eth0 and eth1). By default, all the traffic is routed through interface eth0 irrespective of what IP address you have configured on eth1.

To route the incoming and outgoing traffic through eth1, other than the default route (eth0), you also need to add additional routes for eth1 .
(more…)

15 aptitude Command Examples for Package Management in Linux

by Balakrishnan Mariyappan on August 11, 2014

For Debian based systems like Ubuntu, you can use aptitude command for package management from the command line.

This article explains several aptitude command examples including the following:

  • Install a specific version of a package
  • Install multiple packages using pattern
  • Search for a package using pattern
  • Get packages under a section
  • Don’t update a specific package (Using hold and keep)
  • Mark a package with a specific install type
  • Perform system update
  • Perform safe upgrade

(more…)

Most software products usually have a programmatic automation of input and output interface, which facilitate the monkey test.

With these interface, the product can be fully tested under various user input conditions.
(more…)

There are three types of cryptography techniques :

  1. Secret key Cryptography
  2. Public key cryptography
  3. Hash Functions

(more…)

10 insserv Command Examples for Linux System Init Scripts

by Karthikeyan Sadhasivam on August 6, 2014

insserv command is used to control the start and stop order of the services that are on a Linux system.

It enables an installed system init script (boot script) by reading comment header of the init script and calculating the dependencies between all the scripts.

Insserv scans for the system facilities in the configuration file /etc/insserv.conf and the directory /etc/insserv.conf.d.
(more…)