March 2009

4 Ways to Identify Who is Logged-In on Your Linux System

by Ramesh Natarajan on March 30, 2009

This article is written by Hari Haran.

As a system administrator, you may want to know who is on the system at any give point in time. You may also want to know what they are doing. In this article let us review 4 different methods to identify who is on your Linux system.
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15 Practical Grep Command Examples In Linux / UNIX

by SathiyaMoorthy on March 26, 2009

Photo courtesy of Alexôme’s

You should get a grip on the Linux grep command.

This is part of the on-going 15 Examples series, where 15 detailed examples will be provided for a specific command or functionality. Earlier we discussed 15 practical examples for Linux find command, Linux command line history and mysqladmin command.

In this article let us review 15 practical examples of Linux grep command that will be very useful to both newbies and experts.

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Mergecap and Tshark: Merge Packet Dumps and Analyze Network Traffic

by Ramesh Natarajan on March 23, 2009

Photo courtesy of Michael_P

This article is written by Balakrishnan M

A while back we reviewed 11 examples on how to use editcap utility to capture network dumps. In this article, let us review mergecap utility and tshark commands.

Mergecap is a packet dump combining tool, which will combine multiple dumps into a single dump file. Based on timestamp, the packets are written into the output file in an orderly manner. By default the output file is written in the libpcap format. However using mergecap options, we can generate output in various different format including those that are supported by wireshark tool.
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tree and pstree: Visualize Unix Processes and Directories in Hierarchical Structure

by Ramesh Natarajan on March 19, 2009

Photo courtesy of Steffe

This article is written by SathiyaMoorthy.

Using the traditional ps command, you have to manually look at the PID and Parent PID to identify the dependencies between the processes. Sometimes it may be helpful to view the Linux processes in hierarchical format showing the child processes under the parent process. pstree command (Process Tree) will display the processes hierarchically.

Using the ls command, you typically view the content of a directory structure. Sometimes it may be very helpful to view the directory structure in a hierarchical display. tree command (Directory Tree) will display the directory structures hierarchically.

In this article let us review how to view the processes and directories in tree like format with detailed examples

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PuTTY: Extreme Makeover Using PuTTY Connection Manager

by Ramesh Natarajan on March 16, 2009

PuTTY Logo This article is part of the on-going Software For Geeks series.

PuTTY Connection Manager was mentioned in the 12 PuTTY add-ons that we discussed a while back. One of the major missing features in PuTTY is the ability to display multiple sessions in Tabs.

PuTTY CM displays multiple PuTTY sessions in Tabs. In this article, let us review in detail the 5 powerful features of the PuTTY Connection Manager that will make PuTTY more enjoyable.

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Vim Editor: How to Correct Spelling Mistakes Automatically

by Ramesh Natarajan on March 12, 2009

Photo courtesy of shandrew

This article is written by SathiyaMoorthy.

This article is part of the ongoing Vi / Vim Tips and Tricks Series. I tend to make simple spelling mistakes while writing, as English is not my first language. Wouldn’t be nice if Vim editor can do the spelling correction automatically as you make a typo?

Note: I wish someone from ~~Nayv~~ Navy football team read this article. Oh well, that would’ve still not fixed their problem.

In this article, let us review how to correct spelling mistakes automatically inside Vim editor.

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Ifconfig: 7 Examples To Configure Network Interface

by Ramesh Natarajan on March 9, 2009

Photo courtesy of new1mproved

This article is written by Lakshmanan G

Ifconfig command is used to configure network interfaces. ifconfig stands for interface configurator. Ifconfig is widely used to initialize the network interface and to enable or disable the interfaces.

In this article, let us review 7 common usages of ifconfig command.

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8 Essential Vim Editor Navigation Fundamentals

by Ramesh Natarajan on March 6, 2009

Photo courtesy of Håkan Dahlström

This article is written by SathiyaMoorthy.

This article is part of the ongoing Vi / Vim Tips and Tricks series. Navigation is a vital part of text editing. To be very productive, you should be aware of all possible navigation shortcuts in your editor. In this article, let us review the following 8 Vi / Vim navigation options.