Random Left Right App Worth 1.4 Million

 The recent hype about IBM charging 1.4million, which can be simply achieved within 4 minutes!

Watch the video below to see how it is done by a Chinese guy

[su_youtube url=”https://www.youtube.com/watch?v=_BF1jRQUPUw”]

Get the full story below.
http://www.indiatimes.com/news/india/ibm-charges-us-government-1-4-million-to-create-an-app-indian-techie-recreates-it-in-just-4-minutes-253156.html

Upgrade PHP 5 to PHP 7 on CentOS/RHEL 6/7

As we all know, PHP 7 brings 2x the increase in performance to PHP powered systems. The main purpose of this guide will be focusing on the steps to upgrade your web server from PHP 5 to PHP 7 on CentOS.

Pre-requisite

If you are upgrading an existing system to PHP 7, it is advised to test your current system with this upgrade on a separate web server.

Check that your current PHP source codes is compatible with PHP 7 at the following link.

https://secure.php.net/manual/en/migration70.php

1. Install YUM Repository

CentOS/RHEL 7.x

CentOS/RHEL 6.x

1. Upgrade PHP

2. Install PHP 7

[Optional] APC

If you have existing APC (Alternative PHP Cache) installed in your web server, you will have to remove it as APC does not support PHP 7.

After uninstalling APC, modify the following file.

Comment the following line of code by adding a semicolon ‘;’ in front of it.

Check PHP Version

Run the following command to check your current version of PHP.

You should see the following.

 

That’s it! You are done upgrading from PHP 5 to PHP 7.

How to Change Time Zone on CentOS 6?

Always having difficulty on how to change time zone on CentOS 6? Just bookmark this page and everything will be solved.

Identify your current time zone

There are two ways to identify your current time zone.

or

Change time zone

Change “Amercia/Chicago” to the respective time zone that you want.

 

[Additional] Change PHP time zone

Search for this line

Change it to

Of course change it the time zone you want it to be

 

After running the commands above, remember to run the first step again to check that your time zone has been updated successfully.

That’s it. Changing CentOS 6 time zone is as simple as this.

Install Varnish Cache on CentOS 6/7

Varnish Cache is a tool that helps to cache web pages for quicker loading of web pages.

Here we will cover how to install Varnish Cache on CentOS 6/7.

Step 1: Add EPEL

CentOS 6

CentOS 7

Step 2: Download Varnish Cache

CentOS 6

CentOS 7

Step 3: Install Varnish Cache

CentOS 6/7

Step 4: Start Varnish Cache

CentOS 6

CentOS 7

Step 5: Set Varnish Cache to run on boot

CentOS 6

CentOS 7

 

That’s it! It’s that simple to setup Varnish Cache.

Feel free to contact me at [email protected] if you have any questions.

Complete overview of the mobile app development process (Infographic)

Clients always have the misperception that developing a mobile app is as easy as developing a mobile application would be a walk in a park without much effort involved. The following infographic pretty much sums up the total cost and effort for mobile app development.

Infographic on mobile app development

Credits to TechInAsia for posting this infographic.

Permissions for WordPress on CentOS 6

Often when we install WordPress on CentOS 6 web server, we will encounter permissions issue when we try to do anything.

The following commands will help you set the correct permissions required in order for WordPress to function properly.

After setting the correct permissions for WordPress, remember to restart your web server by running the following command.

 

Install OpenCart 2 on CentOS

This guide focuses on how to install OpenCart 2 on CentOS 6. Before proceeding with this guide, make sure your server have met the following requirements.

1. Download OpenCart

Download OpenCart 2 from the following link, http://www.opencart.com/?route=download/download.

Then unzip the downloaded package.

2. Upload OpenCart to server

Use any FTP client (FileZilla, Transmit, etc) to upload your OpenCart files that you have just unzip to the server.

After uploading the files, renaming the following files:

  • /config-dist.php to /config.php
  • /admin/config-dist.php to /config.php

Note: For Apache servers, the directory that you are to upload to is /var/www/.

3. Enable file read/write permissions

Modify the file read/write permissions for the following files/directories:

  • /var/www/store/config.php
  • /var/www/store/admin/config.php
  • /var/www/store/system/cache/
  • /var/www/store/system/logs/
  • /var/www/store/system/download/
  • /var/www/store/system/upload/
  • /var/www/store/image/
  • /var/www/store/image/cache/
  • /var/www/store/image/catalog/
  • /var/www/store/system/modification/

Command to modify file read/write permissions

And one more additional command to run on image/cache directory

 

4. Begin Installation

Now head over to your web browser and access the following url.

5. Installation Step 1

OpenCart Installation Step 1
OpenCart Installation Step 1

Click on Continue to proceed.

6. Installation Step 2

OpenCart Installation Step 2
OpenCart Installation Step 2

If you have followed the previous steps correctly, then you should see all green ticks and all files/directories status are labelled as Writable.

Click on Continue to proceed.

7. Installation Step 3

OpenCart Installation Step 3
OpenCart Installation Step 3

Fill up your database connection details and an account for administration.

Then click on Continue to proceed.

8. Installation Step 4

OpenCart Installation Step 4
OpenCart Installation Step 4

That’s it! You have successfully setup an E-Commerce store online for yourself.

Feel free to drop me an email at [email protected] or leave a comment if you have any questions.

Setup NGINX Load Balancer with SSL on CentOS 6

Load balancing is a very common mechanism used to distribute traffic for systems. This tutorial goes through step by step from installation of NGINX on your CentOS web server and configuring your NGINX load balancer after it is installed successfully.

1. Add NGINX Repository

2. Install NGINX

3. Start NGINX

4. Configure NGINX config files

Locate NGINX configuration files at /etc/nginx/conf.d/ directory.

Ensure that you have SSL configured for your web server, if not you can follow the tutorial on Setting Up an SSL Secured Webserver with CentOS.

After you are done with the above steps, proceed to edit the following NGINX configuration file for SSL.

Editing NGINX config file

Add the following above your server {} module

Note that the servers will be served in round robin order. You can refer to NGINX documentation for more configurations.

The next few changes is to be done within the server {} module

Enable server to listen to port 443

Add server name

If you have followed my tutorial on Setting Up an SSL Secured Webserver with CentOS, then you can configure your SSL certificate and key as follows.

Next under location / {} module, add the following lines.

After which, save your NGINX configuration file.

Then restart NGINX.

That’s it you are done. If you have any other questions, do feel free to drop a comment below.

Install Zabbix Agent on CentOS/RHEL

Zabbix is an open source software for application and network monitoring. There are two types of Zabbix installation, namely Zabbix server and Zabbix agent. Zabbix server is installed on the server where you will oversee and monitor all the networks or devices. Zabbix agent is installed on all networks or devices so that the Zabbix server is able to communicate with it.

This tutorial guides you step by step on how to install and configure a Zabbix agent on CentOS/RHEL server.

Installing Zabbix Agent

1. Configure Yum Repository

Run the following commands accordingly to the version of CentOS/RHEL you are using.

CentOS/RHEL 7

CentOS/RHEL 6

CentOS/RHEL 5

2. Install Zabbix Agent

Command to install Zabbix agent

3. Update Zabbix Agent Configuration File

Your Zabbix agent configuration file should be located at /etc/zabbix/zabbix_agentd.conf.

Edit configuration file

Modify the following lines

Save and exit nano editor

4. Restart Zabbix Agent

Command to restart Zabbix agent

(Additional Information) Alternately, you can start/stop your Zabbix agent via the following commands.

 

That’s it! You are done installing Zabbix agent on your server.

In case you have missed out on how to install Zabbix server on your server, you can refer to the guide on how to install Zabbix server on CentOS/RHEL.

Feel free to email me at [email protected] if you have any questions.

Install Zabbix Server on CentOS/RHEL

Zabbix is an open source software for application and network monitoring. There are two types of Zabbix installation, namely Zabbix server and Zabbix agent. Zabbix server is installed on the server where you will oversee and monitor all the networks or devices. Zabbix agent is installed on all networks or devices so that the Zabbix server is able to communicate with it.

This tutorial guides you step by step on how to install and configure a Zabbix server on CentOS/RHEL server.

1. Set up Apache, MySQL and PHP

Install Apache

Install MySQL

Install PHP

Start Apache and MySQL services

Setup MySQL by running the following command

2. Configure Yum Repository

RPM repository needs to be configured before installing Zabbix.

Run the following commands according to the version of OS that you are using.

CentOS/RHEL 7

CentOS/RHEL 6

CentOS/RHEL 5

3. Install Zabbix Server with MySQL

Command to install zabbix server

4. Setup Zabbix Apache Configuration

Locate Zabbix’s own Apache configuration file. By default it should be located at /etc/httpd/conf.d/zabbix.conf. Modify the config file by added your time zone.

Added time zone to config file

Restart Apache service after changing the time zone value

5. Create Zabbix MySQL Database

Zabbix MySQL user and database is required as part of Zabbix server installation.

Login to your MySQL first

After which you will be prompt to enter your root password that you have configured previously when you setup MySQL.

Create Zabbix database

Create Zabbix MySQL user to access Zabbix database

Grant privileges to Zabbix user on Zabbix database

Flush privileges

Exit MySQL

After creating MySQL user and database for Zabbix, you will need to restore the default MySQL database provided by Zabbix. The files can be found at /usr/share/doc/zabbix-server-mysql-<version>/create/ directory.

Note: remember to change the version accordingly to the version that you are installing.

6. Start Zabbix Server

Command to start Zabbix server

7. Start Zabbix Web Installer

You can now access your Zabbix web installer via the following url

Zabbix Setup Welcome Screen

Following is the welcome screen of Zabbix web installer. Click on Next to proceed.

Screen Shot 2015-08-15 at 11.55.34 am

Installation pre-requisites

If everything is ok, click Next to proceed.

Screen Shot 2015-08-15 at 11.57.54 am

Configure Database Connection

Enter the database information that you have created previously. Then click on Test Connection. If everything is correct, click Next to proceed.

Screen Shot 2015-08-15 at 12.00.35 pm

Zabbix Server Details

Click on Next to proceed.

Screen Shot 2015-08-15 at 12.01.46 pm

Pre-Installation Summary Screen

If all information is correct, click on Next to proceed.

Screen Shot 2015-08-15 at 12.12.48 pm

Installation Success

Click on Finish to proceed.

Screen Shot 2015-08-15 at 12.03.40 pm

Zabbix Login Screen

You can now login to Zabbix via the following url

Default username and password is as follows

Screen Shot 2015-08-15 at 12.15.08 pm

 

 

That’s it! You are done installing Zabbix server on your server. For installation of Zabbix agent, you can refer to my guide on how to install Zabbix agent on CentOS/RHEL.

Feel free to email me at [email protected] if you have any questions.