If you connect to remote computers over the Internet, it is a pretty good chance you use some form of SSH or secure shell. On Linux or Unix you’ll use the ssh command. Same goes for Linux-lik…

The dig command is an incredibly powerful tool for querying DNS records. Dig stands for Domain Information Groper and is the utility of choice for most DNS administrators working on Linux. It can be used to confirm DNS entries, get your public IP address from the command line, troubleshoot DNS issues and get information about a DNS zone.

Dig is part of the BIND (Berkely Internet Name Domain) software utilities (bind-utils). Although not installed by default, it is available on nearly all Linux distributions by installing the bind-utils package or Red Hat variants or dnsutils on Debian based distros.

Linux configuration, Automation, Security – Sysadmin/DevOps blog

These documents and tools were created by me while I worked at Verio as well as all the time since then. As such, there are still some references to "customers" and maybe even some procedures we used while I worked there. Since the content is just fine, just a bit weird to read, I haven't updated these and am focusing more on adding new content rather than fixing these "bugs".

If you are interested in seeing more content added to the site, and particularly if you have any topics you would like to see covered, then please let me know. I am interested in adding content/tools that will be read and used. So, anytime I run across stuff that I think is useful, I add it.

this document explains how to install and configure a Quake II (q2) dedicated server on a linux box. it is assumed that you :

• have root shell access to a linux box (remote or local)
• know some linux basics (installing software, ssh, ...)
• know some quake basics (config, mods, basic console commands, ...)
• want to install a quake server ;-)
• you have 'screen' installed on your server (simply install it if you don't have it)
• I'm using a debian server in this example but you should be able to adapt this to your favourite distribution easily
• we'll be installing a r1q2 server for security reasons here (Though this includes all steps necessary to install a normal q2 server and also leaves you with a ready-2-run normal q2 server, using the non-r1q2 server for an internet server is highly discouraged due to many security issues with the original q2 binary!)

The Quake II linux dedicated server HOWTO

this document explains how to install and configure a Quake II (q2) dedicated server on a linux box. it is assumed that you :

• have root shell access to a linux box (remote or local)
• know some linux basics (installing software, ssh, ...)
• know some quake basics (config, mods, basic console commands, ...)
• want to install a quake server ;-)
• you have 'screen' installed on your server (simply install it if you don't have it)
• I'm using a debian server in this example but you should be able to adapt this to your favourite distribution easily
• we'll be installing a r1q2 server for security reasons here (Though this includes all steps necessary to install a normal q2 server and also leaves you with a ready-2-run normal q2 server, using the non-r1q2 server for an internet server is highly discouraged due to many security issues with the original q2 binary!)

Please read my notes on security before making your server public.

Introduction
PHP is a complex language that has suffered years of twists, bends, stretches, and hacks. It's highly inconsistent and sometimes buggy. Each version has its own unique features, warts, and quirks, and it's hard to keep track of what version has what problems. It's easy to see why it gets as much hate as it does sometimes.
Despite that, it's the most popular language on the web today. Because of its long history, you'll find lots of tutorials on how to do basic things like password hashing and database access. The problem is that out of five tutorials, you have a good chance of finding five totally different ways of doing something. Which way is the "right" way? Do any of the other ways have subtle bugs or gotchas? It's really hard to find out, and you'll be bouncing around the internet trying to pin down the right answer.
That's also one of the reasons why new PHP programmers are so frequently blamed for ugly, outdated, or insecure code. They can't help it if the first Google result was a four-year-old article teaching a five-year-old method!
This document tries to address that. It's an attempt to compile a set of basic instructions for what can be considered best practices for common and confusing issues and tasks in PHP. If a low-level task has multiple and confusing approaches in PHP, it belongs here.
What this is
It's a guide suggesting the best direction to take when facing one of the common low-level tasks a PHP programmer might encounter that are unclear because of the many options PHP might offer. For example: connecting to a database is a common task with a large amount of possible solutions in PHP, not all of them good ones—thus, it's included in this document.
It's a series of short, introductory solutions. Examples should get you up and running in a basic setting, and you should do your own research to flesh them out into something useful to you.
It points to what we consider the state-of-the-art of PHP. However, this means that if you're using an older version of PHP, some of the features required to pull off these solutions might not be available to you.
This is a living document that I'll do my best to keep updated as PHP continues to evolve.
What this isn't
This document is not a PHP tutorial. You should learn the basics and syntax of the language elsewhere.
It's not a guide to common web application problems like cookie storage, caching, coding style, documentation, and so on.
It's not a security guide. While it touches upon some security-related issues, you're expected to do your own research when it comes to securing your PHP apps. In particular, you should carefully review any solution proposed here before implementing it. Your code is your own fault.
It's not an advocate of a certain coding style, pattern, or framework.
It's not an advocate for a certain way of doing high-level tasks like user registration, login systems, etc. This document is strictly for low-level tasks that, because of PHP's long history, might be confusing or unclear.
It's not a be-all and end-all solution, nor is it the only solution. Some of the methods described below might not be what's best for your particular situation, and there are lots of different ways of achieving the same ends. In particular, high-load web apps might benefit from more esoteric solutions to some of these problems.

A beautiful illustrated guide to how cars work
We have 287 articles and 2232 illustrations that show how the various parts of a car function, and will show you exactly how a car works. Every part is covered - from the bumper to the tailpipe, passing the engine, transmission, brakes and steering.

W związku z coraz większą liczbą powiadomień o nienaturalnych linkach postanowiliśmy zebrać w jednym miejscu nasze doświadczenia związane z wycofywaniem działań ręcznych.

Opiszę tutaj stosowaną przez nas procedurę, która sprawdziła się w przypadku wielu serwisów, w tym dużych witryn e-commerce.

(Analogiczną procedurę — oczywiście bez ostatniego kroku — stosujemy dla przejmowanych stron bez działań ręcznych, aby zabezpieczyć się przed ew. filtrami algorytmicznymi i ręcznymi w przyszłości).

W zdecydowanej większości przypadków zgłaszane pliki disavow.txt zawierają tylko wpisy obejmujące całe domeny, więc w poniższej procedurze zakładam właśnie takie rozwiązanie.

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.

Laravel is a modern and robust PHP framework. There are several tutorials available here on CodeForest, but I still receive plenty of questions on getting started with Laravel, How to use Composer and similar.

There’s a lot of outdated information on the Web that leads new PHP users astray, propagating bad practices and insecure code. PHP: The Right Way is an easy-to-read, quick reference for PHP popular coding standards, links to authoritative tutorials around the Web and what the contributors consider to be best practices at the present time.

There is no canonical way to use PHP. This website aims to introduce new PHP developers to some topics which they may not discover until it is too late, and aims to give seasoned pros some fresh ideas on those topics they’ve been doing for years without ever reconsidering. This website will also not tell you which tools to use, but instead offer suggestions for multiple options, when possible explaining the differences in approach and use-case.

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.

Linux Apache MySQL PHP + Bitcoin tutorial.
For this introduction we assume that you have GNU/Linux server with Apache and PHP and that you wish to interact with the Bitcoin network from a web application. We assume some knowledge of Bitcoin and experience in PHP.
While this is written for PHP, the same principles apply for other languages. See the associated API reference pages for info on other languages.
The easiest way to get started is to run Bitcoin in daemon mode with which PHP communicates via local HTTP requests. A library called JSON-RPC is used to call the various functions of bitcoind, which will respond back with a JSON object.

More than two years ago I wrote a post about sending push notifications from php to an iOS app called Pushme.To. That code, now, no longer works, and Pushme.to service no longer exists. Now I’m using an Android device and so, I’m going to show you how to send push notifications in a simple way to another app, for Android. The app is called Notify My Android and it’s free.

What is Symfony2 Framework?
A set of bundles containing configuration and bridge classes
These glue the components together, giving the developer a consistent experience
Symfony 2 is a PHP Framework for web development
Symfony 2 is MVC
Symfony 2 is OOP
Symfony 2 is not Symfony 1 (>=PHP 5.3)
Symfony 2 is HTTP-centric
Symfony 2 is like bits of Rails and like bits of Java
Why Symfony2?
Based on project needs Symfony can be used as:
Full framework
Micro framework (single file apps)
Symfony Components (stand alone)
Symfony comes with tight integration with many open source projects like Monolog, Assetic, Doctrine, Propel.
Powerful and easy routing.
Very advanced and useful template engine TWIG

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.

Responsive elements makes it possible for any element to adapt and respond to the area they occupy. It's a tiny javascript library that you can drop into your projects today.

Since the 70′s, vi and vim are very popular text editors among programmers. 5 years ago, I wrote an article named “100 vim commands every programmer should know” and here is a reworked, updated version. Enjoy!

VnStat PHP a graphical interface application for most famous console mode network logger utility called “vnstat“. This VnStat PHP is a graphical frontend to VnStat, to view and monitor network traffic bandwidth usage report in nicely graphical format. It display IN and OUT network traffic statistics in hourly, days, months or full summary.
This article shows you how to install VnStat and VnStat PHP  in Linux systems.