How to Setup Let’s Encrypt FREE SSL Certificate on Centos 6 Apache using Certbot?

Having SSL on your website these days is important especially if you want your website to rank better on Google search, and that’s when Let’s Encrypt come into the picture.

Let’s Encrypt is a free, automated, and open certificate authority (CA), run for the public’s benefit. It is a service provided by the Internet Security Research Group (ISRG).

Without further ado, let’s begin with the tutorial.

Step 1: Install Certbot

Installing Certbot via certbot-auto script.

Step 2: Get Certificate & Edit Apache Config

It should bring you through a series of steps to have your SSL certificate setup.

Select the site you want to have SSL certificate installed on.

Step 3: Configure CRON Job for Cert Renewal

The following are commands to renewal your SSL certificate.

Dry Run

Actual Command

Add actual command to crontab.

Enter :i and paste the following in the file following by ctrl+c and :wq to quit and save editor.


That’s it all is done.

8 Simple Steps to Setup a Web Server with Apache Virtual Hosts & MySQL in Centos

This tutorial will be guiding you in setting up a web server with pre-installed Centos. In summary, you will be installing Apache and MySQL, and learning how to configure virtual hosts in Apache.

Note: before proceeding with this tutorial. Make sure you figure out how to SSH into your server first.

Step 1: Update Centos

Step 2: Install development tools on Centos

Step 3: Install some useful tools

mlocate – This is used to assist you in looking for files in Centos. You will see it in action later.

nano – This a text editor in Centos that is much easier to use than vi or vim.

Step 4: Install Apache

Step 4.1: Install Apache

Step 4.2: Start Apache service

Step 4.3: Set Apache to run on server boot/restart

Step 5: Install MySQL

We are going to install MySQL 5.5 here.

Step 5.1: Add repos and install MySQL 5.5

Step 5.2: Start MySQL service

Step 5.3: Configure MySQL

After running the above command, you will get a bunch of prompts.

  1. Simply hit enter on initial root password prompt as we don’t have any yet from a fresh installation.
  2. Enter your new password for root user.
  3. Simply enter “y” = yes for the remaining options.

Step 6: Set Timezone for server

In the above command, I have set the timezone to Singapore, simply because I’m from Singapore. Feel free to change it to your own timezone.

Step 7: Install SSL support

This will enable SSL support on your web server if you wish to add your own SSL certificate here in future.

Step 8: Setup Virtual Host on Apache

Before proceeding, now we can use mlocate which we have installed previously.

Running the above command sort of index the files in your server for mlocate to work.

Use mlocate to look for Apache’s configuration file.

You should be getting something like this, “/etc/httpd/conf/httpd.conf”.

So now we can make use of nano that we have installed previously.

The above will allow start editing of Apache configuration file.

Step 8.1: Editing Apache Configuration

  1. Hit ctrl+w and type “/var/www” and enter
  2. Change DocumentRoot “/var/www/html” to DocumentRoot “/var/www”
  3. Hit ctrl+w again
  4. Change <Directory “/var/www/html”> to <Directory “/var/www”>
  5. Hit ctrl+w again and type “AllowOverride None” and enter
  6. Change AllowOverride None to AllowOverride All
  7. Hit ctrl+w again and type “NameVirtualHost *:80” and enter
  8. Change #NameVirtualHost *:80 to NameVirtualHost *:80
  9. Add one more line below it, NameVirtualHost *:443
  10. Then hit ctrl+v multiple times till you reach the end of the document

Do not close the file yet.

So what you have done above is doing some basic configuration to Apache for virtual host to work.

Now we need to setup virtual host in Apache configuration.

Below is a sample virtual host configuration.

Notice that “” is the subdomain/domain you are trying to configure. So simple just change all occurrence of that to your own subdomain/domain.

To proceed, paste that at the end of Apache configuration file.

To finish editing Apache configuration file.

Hit ctrl+x and enter.

Last step, restart Apache.

Step 8.2: Setup directories and files for a Virtual Host

Remember that we set our Apache document root to “/var/www” above.

Navigate to that directory now.

Create virtual host directory for your subdomain/domain.

Get into the folder.

Create error and requests log files.

Create folder to host files for this virtual host.

Inside public_html folder, this is where you should place all your .html, .js and .css files for hosting.

Step 8.3: Setting permission for hosting directory

This will set Apache to be owner of those folders you have just created.

Step 8.4: Flush iptables

Flushing iptables will remove all firewall records on your server. Then you will be able to access your site.

Finishing Up

If you remember we setup the virtual host for “”. Do remember to setup your DNS record that points “” to your server ip address.

That’s it you are done!

How to create Apache htpasswd file in Linux OS?

What is htpasswd?

At times during web development, we will need to prevent the whole world from being able to access a particular website. That’s when Apache htpasswd comes into the picture. htpasswd is usually used together with htaccess.


This tutorial will teach you how to create a htpasswd file using command line.

Creating a htpasswd for the first time


Appending new user to existing htpasswd file


Using htpasswd in htaccess


That’s it you are done!

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,

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.

Install and Secure phpMyAdmin on CentOS 6.4

PhpMyAdmin is a popular web interface for web developers to manage MySQL databases. This tutorial will guide you through on how to install and secure PhpMyAdmin on your CentOS web server.


This guide assumes that you already have Apache and MySQL installed on your CentOS web server.
(Optional) Note that if you want to access PhpMyAdmin using SSL, then you will need to configure SSL certificate by referring to the following guide.

Setting up an SSL Secured Web Server with CentOS

1. Add EPEL Repositories

PhpMyAdmin is not included in CentOS packages, therefore you will need to add EPEL (Extra Packages for Enterprise Linux) to your web server.

(Optional) Run the following command to install wget if you haven’t install wget yet

Command to install EPEL packages to your web server

Check that EPEL has been added to your repository

You should see the following

Once done remove the respository configuration package

2. Download PhpMyAdmin

Command to download PhpMyAdmin

3. Configure PhpMyAdmin

Find your IP Address first
Then edit PhpMyAdmin config file

Modify the following 4 lines in the config file

Then save and close the config file

4. Open PhpMyAdmin in your Web Browser

Open the following url in your web browser


That’s it you are done!

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

Install Linux, Apache, MySQL, PHP (LAMP) stack on CentOS 6

LAMP stack is a group of open source softwares used to get web servers up and running. This guide assumes that you already have your CentOS installed successfully.

1. Install Apache

Apache is the web server in the lamp stack.

Install apache command

Start apache on your server

(Optional) Test if apache is alive

Get your IP address first

Then open the following url in your web browser

2. Install MySQL

MySQL is the database management system used in LAMP stack.

Install MySQL command

Start MySQL service

Set a root MySQL password

This will prompt you for your current MySQL root password, which you will most likely have none, because you have just installed MySQL only. So just leave it blank by pressing enter.

Next a series of yes/no questions will appear. All you have to do is just say Yes to all the options.

3. Install PHP

Install PHP command

(Optional) Install additional php modules

Search for PHP modules command

Next a bunch of php modules with their description will appear. So just use yum to install which ever modules that you want.

4. Configure Apache and MySQL to run on boot

5. Test if PHP is working on your server

By default apache web root directory is at /var/www/html

Create a file called info.php 

(Optional) If nano is not installed yet

Add the following code to info.php

Then save and exit

Restart Apache and visit the url on your web browser as follows

Then you should see your server’s php information


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

Installing Webmin on CentOS/RHEL 5/6/7 and Fedora 20/21

Wedmin is a web-based interface for you to manage your linux systems. It allows you to setup user accounts, configure cron jobs, manage Apache and many more.


1. Download Webmin RPM

2. Install Webmin using RPM Command

3. Access Webmin in Browser

Additional Information

Below are the commands to start, stop, restart and get status of Webmin service