Hi Mixxxers -- did you miss us? The Mixxx team has been quietly toiling for over 2 years to bring you Mixxx 1.12. This will be our biggest release ever and we need your help to make sure that it's our best ever as well. We've been doing alpha testing with our dedicated forum users for a while now and are ready to release Mixxx 1.12 Beta!

In this 4th part of our KVM series, we are discussing KVM environment management using CLI. We use ‘virt-install’ CL tool to create and configure virtual machines, virsh CL tool to create and configure storage pools and qemu-img CL tool to create and manage disk images.

Like many people, you store sensitive information in your database. And like some, your database server is on a different host from one or more of your webservers. How do you secure the necessary network connections?

The obvious answer is SSL/TLS. But that requires you to a) use a custom MySQL binary, and b) manage yet another set of certificates. And it requires setting extra parameters when connecting to the database in your code.

A less obvious answer is to use the ssh's built-in port forwarding to tunnel the connection. Here's how.

Note that the commands and scripts in this document assume that you are connecting to a MySQL database named "db" on remotehost.com, port 3306, using username "dbuser" and password "PASS". You will need to change these values to match your own setup.

Linux command shelf is a quick reference guide for all linux user who wish to learn linux commands. Commands are divided into 15 categories , which would be more easier to understand what commands to be used in specific requirement. The pdf format of linux command shelf is also available. You could reach Bobbin Zachariah the author of this guide for any comments or corrections.

You can download the latest version of linux command shelf in pdf format. Current linux command shelf version is 1.1. This guide can be used by both advanaced and new linux users , provided the best efforts to give most relevant linux commands.

You can navigate to each section using the index that is places on the right hand side of this page or just below. If you feel hard to understand any command please let me know on my above profile page.

A 48-bit MAC address (e.g., 08:4f:b5:05:56:a0) is a globally unique identifier associated with a physical network interface, which is assigned by a manufacturer of the corresponding network interface card. Higher 24 bits in a MAC address (also known as OUI or "Organizationally Unique Identifier") uniquely identify the organization which has issued the MAC address, so that there is no conflict among all existing MAC addresses.

While a MAC address is a manufacturer-assigned hardware address, it can actually be modified by a user. This practice is often called "MAC address spoofing." In this tutorial, I am going to show how to spoof the MAC address of a network interface on Linux.

ZoneMinder is the top Linux video camera security and surveillance solution. In this document I will cover how to get ZoneMinder up and running on Ubuntu 6.06.1 LTS or Dapper Drake with the recent updates included.

Cacti is a complete network graphing solution designed to harness the power of RRDTool's data storage and graphing functionality. Cacti provides a fast poller, advanced graph templating, multiple data acquisition methods, and user management features out of the box. All of this is wrapped in an intuitive, easy to use interface that makes sense for LAN-sized installations up to complex networks with hundreds of devices.

The Linux find command is a very useful and handy command to search for files from the command line. It can be used to search for files based on various criterias like permissions, user ownership, modification date/time, size etc. In this post we shall learn to use the find command along with various options that it supports.

The examples are broken down into discrete examples making it easy to learn and comprehend. The find command is available on most linux distros by default so you do not have to install any package. This is a command you must master, if you want to get comfortable with your linux system.

So lets begin with the command.

The basic format of the syntax is like this

Any system admin working in a service provider network would certainly agree that Cacti is one of the most widely used tools in network management solutions. It is open source, has built in user authentications and user permission features, shipped with frequently used graph templates like bandwidth, 95th percentile, hard disk usage, CPU usage, load average, RAM statistics and many more. Cacti also supports 3rd party templates and plugins. If those are not enough, one can write and use one’s own templates, and that is the beauty of open source software.

How do I setup and manage a virtualized environment with Kernel based Virtual Machine (KVM) in CentOS or Red Hat Enterpise Linux version 6 server on IBM server? Can you provide step-by-step commands of how to install and manage Virtual Machines (VMs) on a physical server using KVM for RHEL/CentOS version 6.4?

Tutorial details
Difficulty Advanced (rss)
Root privileges Yes
Requirements VT enabled server
Estimated completion time 1h
KVM is part of RHEL and CentOS Linux. You can easily install the same using the following commands. Please note that only the package names have changed in RHEL/CentOS 6.x. If you are using RHEL / CentOS 5.x, read our previous CentOS / Redhat (RHEL) v.5.x KVM Virtulization guide for more information.

Overwhelmed with the response of last two articles of “Lesser Known Linux Article” series namely.

When you are tasked with monitoring network traffic on the local network, you can consider many different options to do it, depending on the scale/traffic of the local network, monitoring platforms/interface, types of backend database, etc.

ntopng is an open-source (GPLv3) network traffic analyzer which provides a web interface for real-time network traffic monitoring. It runs on multiple platforms including Linux and MacOS X. ntopng comes with a simple RMON-like agent with built-in web server capability, and uses Redis-backed key-value server to store time series statistics. You can install ntopng network traffic analyzer on any designated monitoring server connected to your network, and use a web browser to access real-time traffic reports available on the server.

As an owner of the website it is very difficult to manage multiple websites without a control panel. However to suit the needs, we need a custom hosting plan.
A Web hosting control panel is a totally web-based interface which has capability to manage your web services under a single location. These web based control panels can manage email accounts, FTP accounts, file management functions, creation of subdomains, disk space monitoring, bandwidth monitoring, create backups and many more.

Ajenti includes dozens of pre-made plugins that let you configure both your OS and server software. List of supported software includes Apache, Cron, CTDB, NFSD, Iptables, Munin, MySQL, Netatalk, NGINX, PostgreSQL, Samba, lm-sensors, Squid 3, Supervisor.
Fast and responsive interface, low memory footprint and handy tools like file manager, terminal and code editor - everything a happy sysadmin needs.

In this recipe, we forward messages from one system to another one. This is used in a number of cases:
the local system does not store any messages (e.g. has not sufficient space to do so)
there is a (e.g. legal) requirement to consolidate all logs on a single system
the server may run some advanced alerting rules, and needs to have a full picture or network activity to work well

Have you ever seen a train running on Linux command line? Have you ever seen ‘Tom and Jerry’ on Linux command line? Well, working on Linux command line is not that serious always. There lies a fun factor too. Here in this space, we shall discuss the idiosyncrasies of Linux command line.

Assumption: Ubuntu Linux is used for all the examples in this article. The command line utilities described in this article may or may not be present by default on your Linux system.

After I install a new version of Linux, I usually take a good look at the screen. Does it have a task bar? Can you find your window after it was minimized? Lately, some developers have been struck by some sort of amnesia brought on by the stress created by the mobile sector offerings.

Fortunately, in Linux we do have plenty of other choices. I will describe some of them in this article, and I’ll attempt to measure the RAM memory requirements. I use free command in an xterm before and after the graphic environment is started on a separate X server (Xephyr). The computer is an older 64-bit machine, running Ubuntu 12.04 with LXDE as desktop environment.

Note: the tool I use to set it all up is virtenv. I would say it is pretty much experimental at this moment, alpha stage maybe early beta. It sets up a Xephyr xserver running Joe’s Window Manager in a Linux kernel container (LXC). I only have to shut down JWM, apt-get install the new window manager, and run it. The beauty is the container works in a separate filesystem, and it will not overwrite the real filesystem on my computer.

Let’s assume you have a physical machine running a Linux system, and you would like to convert this system into a virtual KVM/QEMU machine, keeping everything as close to the original as possible. What follows is my approach.

The first thing we need is a raw image file which mirrors the exact layout of the physical hard drive in our physical server.

In our example scenario, the physical box has one hard drive at /dev/sda with a /boot Partition on /dev/sda2 and a physical LVM volume on /dev/sda3. This LVM volume houses a volume group with two logical volumes, one of them housing the root partition /, and the other one being unused. Also, /dev/sda1 is unused. Grub is installed into the Master Boot Record.

So what is awk, and what does it have to do with UNIX? Plenty, as you'll soon learn. It is a tool that helps you get certain tasks done in the UNIX shell. But it's no mere tool; it's so developed that it's a programming language in its own right. Keep reading to learn how to make the most of awk.
The core idea in the creation of any programming/scripting language is to make it as natural and as simple as possible. Still, it should allow the construction of advanced expressions for solving complex problems. The creators of the UNIX Shell script language did not forgot these two simple principles. For the sake of simplicity some parts are broken down into multiple sub-parts. Sometimes these sub-parts evolve and grow to form their own programming language.

A prime example for this is Awk. The name "awk" comes from the starting letters of the names of the three creators: Aho - Weinberg - Kernighan. These people defined it as "awk, a pattern scanning and processing language." Besides setting a concrete purpose for the tool, this also underlines the fact that awk has its own syntax and rules. With this, it becomes a programming language on its own.

Awk was designed to scan and process files like the .cvs, where data are organized into columns and rows. However, doing the same with any other source of organized data in this structure is a valid option (as in the case of the command ls -l). The principle behind awk is to divide an input stream into rows and records and make the changes on this.

Last time I presented the stream editor, which accomplished the row splitting. However, compared to the sed, awk is a much more complex, powerful and more capable language. The record extraction allows us to throw away the unnecessary and process only the useful information from a file/UNIX tool.

Awk is a scripting language, and is best for solving small everyday problems. Its three creators do not recommend it for use in big, complex problem solving. However, there are long lists of problems that can be solved with it. It also has a couple of other advantages when compared to other tools, like the sed. For instance, it can work with real numbers and follow a very C-like syntax.

In this and a future article I will try to present it as concisely as I can without leaving out any crucial parts of awk. Remember that this article is only designed to introduce to you this language on a basic level. I do not intend to show you every corner of the scripting language. Nevertheless, this will be enough for you to use it in the everyday problems you may come across in the future.

Making a change sometimes takes a great effort coupled with a great sacrifice. At other times, though, it simply calls for a little adjustment of what we already have. The stream editor does just this. Since inside the UNIX shell, the universal language spoken is the text stream, with the help of this tool you can make some easy and fast modifications to the shell. If you are interested in what you can change and how you can change it with the stream editor, you will have to read this article.
This article is part of my series related to shell programming in UNIX. Therefore, I will build on the fact that you can already write a script and run it inside a terminal. In addition, you should also know how to handle the control mechanism of the UNIX shell. All of these things are explained in my previous articles, so if by chance you missed them just search them up and embrace their knowledge.