Linux

A web stack is nothing but collection of many open source software such as an operating system, Web server, database server, server side programming language. The most commonly known web stacks is LAMP. It is an acronym for a solution stack of free, open source software, referring to the first letters of Linux (operating system), Apache Web server, MySQL database software and PHP (or sometimes Perl or Python). All of our security related tutorials recommends running different network services on separate systems or vm instance. Naturally, this limits the number of other services that can be cracked in the event that an attacker is able to successfully exploit a software flaw in one network service. This is also one of the most requested article via email. In this guide, I will explain how to setup a solution that can serve static content, dynamic content, database, and caching by running on separate servers or vm instance.
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The Lighttpd web server is responsible for providing access to static content via the HTTP or HTTPS protocol. In this example, I’m going to install and use the Lighttpd web server and set DocumentRoot to vm05:/exports/static mounted at /var/www/static. You need to type the following commands on vm01 having an IP address 192.168.1.10 only.
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Nginx is an open source Web server and a reverse proxy server. You can use nginx for a load balancing and/or as a proxy solution to run services from inside those machines through your host’s single public IP address such as 202.54.1.1. In this post, I will explain how to install nginx as reverse proxy server for Apache+php5 domain called www.example.com and Lighttpd static asset domain called static.example.com. You need to type the following commands on vm00 having an IP address 192.168.1.1 only.
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SShell script wrappers can make the *nix command more transparent to the user. The most common shell scripts are simple wrappers around the third party or system binaries. A wrapper is nothing but a shell script or a shell function or an alias that includes a system command or utility.

Linux and a Unix-like operating system can run both 32bit and 64bit specific versions of applications. You can write a wrapper script that can select and execute correct version on a 32bit or 64bit hardware platform. In clustered environment and High-Performance computing environment you may find 100s of wrapper scripts written in Perl, Shell, and Python to get cluster usage, setting up shared storage, submitting and managing jobs, backups, troubleshooting, invokes commands with specified arguments, redirecting stdout/stderr and much more.

In this post, I will explain how to create a shell wrapper to enhance the primary troubleshooting tool such as ping and host.
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Boxes command is a text filter and a little known tool that can draw any kind of ASCII art box around its input text or code for fun and profit. You can quickly create email signatures, or create regional comments in any programming language. This command was intended to be used with the vim text editor, but can be used with any text editor which supports filters, as well as from the command line as a standalone tool.
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An bash shell alias is nothing but the shortcut to commands. The alias command allows the user to launch any command or group of commands (including options and filenames) by entering a single word. Use alias command to display a list of all defined aliases. You can add user-defined aliases to ~/.bashrc file. You can cut down typing time with these aliases, work smartly, and increase productivity at the command prompt.
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