Have you wondered why certain programs are located under /bin, or /sbin, or /usr/bin, or /usr/sbin?

For example, less command is located under /usr/bin directory. Why not /bin, or /sbin, or /usr/sbin? What is the different between all these directories?

In this article, let us review the Linux filesystem structures and understand the meaning of individual high-level directories.
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Squid is a proxy caching server. If you are Linux sysadmin, you can use squid to control internet access at your work environment.

This beginners guide will give a jump-start on how to setup squid on Linux to restrict internet access in an network.
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All IT projects needs a bug tracking (or issue tracking, or defect tracking) system.

Sure, we need a bug tracking system for a software development project. But, what about a sysadmin team, dba team, network team? They all need some help to track their work, and issues of their system, database and network.

I’ve listed 10 open source bug tracking systems, that you can experiment, and choose based on your taste and requirement. This is not a comprehensive list by any means. I’ve used all the systems listed in the top 5, and I strongly recommend that you choose one from the top 5 list.
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cpio command is used to process archive files (for example, *.cpio or *.tar files).

cpio stands for “copy in, copy out”.

cpio performs the following three operations.

• Copying files to an archive
• Extracting files from an archive
• Passing files to another directory tree

cpio takes the list of files from the standard input while creating an archive, and sends the output to the standard output.
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tcpdump command is also called as packet analyzer.

tcpdump command will work on most flavors of unix operating system. tcpdump allows us to save the packets that are captured, so that we can use it for future analysis. The saved file can be viewed by the same tcpdump command. We can also use open source software like wireshark to read the tcpdump pcap files.

In this tcpdump tutorial, let us discuss some practical examples on how to use the tcpdump command.
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Do you need more time to do the things that you enjoy? Of course, you do. For geeks there are tons of technical projects to mess with, but we don’t have enough time.

Over the years, I’ve tried few time management and productivity systems. While they all helped me grow, there is something in those system that didn’t go well with my working style and thinking.

Few years back, I came across David Allen’s Getting Things Done (GTD), immediately it just felt right for my working style and thinking. I cannot imagine my life without GTD anymore.

GTD is not about telling you what software or tools to use to become productive. GTD is a productivity framework that you can tweak it to match your working style.

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Are you always sending SMS to your friend’s cellphone from your cellphone? Did you know that you can SMS to someone using email?

This list is extremely helpful, if you are outside US and would like to SMS someone in US, you can just send it as an email.
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