How to fix the “SSH Remote Host Identification Has Changed” error

In this tutorial, I will try to explain how you can fix the SSH error to the remote machine which has a different digital fingerprint now as compared to the previous fingerprints.

WP-CLI common commands

WP-CLI is a set of command-line tools for managing WordPress installations. You can update plugins, set up multisite installs and much more, without using a web browser.

Redirect from non www to www URL on Nginx

At times we come across requests from customers when they would like to redirect their non www URLs to www URLs. For example if a customer asks to force redirect his site from to To perform this setup on Nginx webserver, follow below steps:

Enable SPDY with NGINX on Centos 6 Servers

The SPDY protocol has been created by Google to load HTTPS pages faster and improving web security.
It will work only when you have running site with SSL.

How to Block countries on Nginx with GeoIP module

GEOIP : The GeoIP technology allows the web masters to get valuable information about the location of their visitors. It can determine the country, city, area code and much more.The web site developers use it for delivering of customized content based on the geographical location, targeted advertisements, web logs and statistics, spam prevention, location restricted access and other useful solutions.

This tutorial will help you to know how we can use the GeoIP module with nginx to block all visitor from single and multipal countries.

Use Linux cron Instead of WP-CRON

WordPress has internal function called WP-CRON, By default every time a page is loaded in admin or on the front-end of your site, WordPress calls WP-CRON. To avoid this, best way optimize the efficiency of your WordPress cron jobs is to disable WP-CRON and set up a Linux cron job. 


  • You need to have a working knowledge of Linux commands before you can use cron jobs effectively.

How to read a file line by line in bash script using while loop

This tutorial introduces the concept of playing a file line by line in bash script using while loop.


This tutorial assumes that the reader has basic knowledge of bash scripting & programming skills.

How to disable logging in Squid Proxy

Some times we come across strange requirements and disabling logs of squid proxy service is one of them. Below are the simple steps to disable all kind of logging by squid service.

How to generate and send Nagios hosts and services reports through command line


The objective of this how to is to setup nagios reporting through command line & enabling the cron jobs to send the reports in HTML format to email accounts specified.


How to install Nodejs on CentOS


The objective of this small HowTo is to help the system administrators setup NodeJS on their CentOS Server.

NOTE: The mentioned steps are successfully ran on CentOS 6 version