You can set up a wireless connection between two routers. One can link a wireless network to a wired network allowing you to bridge two networks with different infrastructure. You can find wireless access points products that offer either a “bridge” mode or a “repeater” mode. In this post, I’m going to explain three popular open source choices that can use for setting up a wireless bridge.
[continue reading…]

Most embedded Linux / BSD systems such as routers, servers and nas devices comes with console interface (serial port with RS-232). BIOS can uses this, and after boot BIOS screen I/O is redirected so that you can use the device. RS-232 is also used for communicating to headless server, where no monitor or keyboard is installed, during boot when operating system is not running yet and therefore no network connection is possible. You need to use a serial cable between your computer and embedded system or server. In this post I will cover five conman utilities used for serial communication under Linux / Unix / *BSD and Mac OS X.
[continue reading…]

Disk cloning is nothing but the process of copying the contents of one hard disk (or partition) to another disk or to an “image” file. I make backup regularly using rsnapshot tool, but I also clone my hard disk once or twice a month. This option allows me to restore my OS and installed software quickly. Linux comes with various utilities for performing disk cloning. In this post, I’m going to list my favourite open source disk cloning softwares that has saved my butt multiple times.
[continue reading…]

Process identifier (PID) is a number used by Linux / Unix kernels (and Windows operating systems) to identify a process. Usually, new processes are created using the fork() system call. Each PID (or so called tasks) can be monitored under Linux. In this quick tutorial, I will explain how to use the pidstat command for monitoring individual tasks currently being managed by the Linux kernel.
[continue reading…]

Amazon web services (AWS) launched a new service called Amazon Glacier. You can use this service for archiving mission-critical data and backups in a reliable way in an enterprise IT or for personal usage. This service cost as low as $0.01 (one US penny, one one-hundredth of a dollar) per Gigabyte, per month. You can store a lot of data in various geographically distinct facilities and verifying hardware or data integrity, irrespective of the length of your retention periods. The first thing comes to mind is, the Glacier would be a good place for a backup off family photos and videos from my local 12TB nas.
[continue reading…]

Mozilla Firefox version 11.x+ has support for 3D view. It is a WebGL based website visualization tool that highlights page structure. You can see relationship between your code and the page output by stacking elements as they are nested in the DOM and lets you see elements that are hidden or off the page. You can zoom in and out, rotate and pan the view to see the page from any angle that is helpful to you. In this blog post I will explain how to enable 3D view on X11. Please note that the 3D view is not for your daily browsing needs. It is useful for finding out bugs such as nesting issues or even XSS vulnerabilities. Personally, I use 3D view as a tool to understand divs, spans, and other elements on the page.
[continue reading…]