Running Selenium with FireFox browser in CentOS

Quick note here the necessary steps to install and run Selenium with FireFox browser in CentOS. We will need to setup XWindows for Headless Selenium with FireFox webdriver. First, install Xvfb: [bash]yum -y install firefox Xvfb libXfont Xorg[/bash] Then, install X-desktop: [bash]yum -y groupinstall "X Window System" "Desktop" "Fonts" "General Purpose […]

Install Jenkins for PHP Continuous Integration

Today I will mention how to install Jenkins and necessary plugins/tools for doing Continuous Integration. This is just a very first step of using Jenkins for PHP Continuous Integration work. I choose to start with a Virtual Machine with Ubuntu 16 and use LAMP with PHP7 for the web stack. […]

OpenVPN installation quick tutorial

Just a quick introduction for OpenVPN installation since there is a good work from that helps install in 1-click. I just add some extra notes when installing as well as connecting for future references. First, run the one-step installation command: [bash]wget -O && bash[/bash] When installing, just remember to […]

Install OpenVPN server CentOS 7

Today I will brief necessary steps for installing OpenVPN server CentOS 7. This will include custom server name and also rules for csf firewall which is widely used. The OpenVPN server name in this tutorial will be myvpnserver, associated domain will be, and server IP address is XXX.YYY.ZZZ.UUU . We […]

Install Chef server Lets Encrypt

Do not want to mention what Chef is, or what Let’s Encrypt is. This is just a short step-by-step tutorial to guide you how to install Chef server Lets Encrypt for the server SSL. Setup Let’s Encrypt First, install let’s encrypt to generate a standalone certificate before installing chef server: […]

Migrate Gitlab to new server

When migrating gitlab to a new server, you might face much problems of in-compatible versions, different OS (so different latest gitlab version), etc. The best way is to upgrade the old server to the same latest gitlab version, then backup gitlab, and then transfer the backup to the new server, […]

Connect to Amazon Cloud Drive from Debian Command line

UPDATE: It seems Amazon has banned ACD_CLI. I contacted Amazon to see what is their suggestion. So waiting for a feedback from them now. We are going to connect to Amazon Cloud Drive from Debian Command line to utilize the benefit of unlimited cloud storage. Even there are various tutorials […]

Real IP from Amazon Load Balancers

If you are running an EC2 instance behind an Amazon Elastic Load Balancer (ELB), you’ll find that the visitors’ IPs are hided behind the load balancer, so your application cannot get the clients’ real IPs. In fact, visitors’ original IPs are passed via a X-Forwarded-For information in the header (, […]

PHP CacheTool – A Cache Management CLI

If you are dealing with various cache, you might find that a CLI tools for viewing status and doing management works is a great idea. You will no longer need to restart your PHP-FPM pool for opcode/apc cache invalidation. You also do not need to write a stupid PHP file […]

Some small tweaks for apache

I have not worked on apache for a long time (if you don’t know, I am a big fan of NginX with PHP-FPM instead of surviving with apache :lol:), so in fact I do not have much experience on tweaking apache. Today when monitoring a server with an apache-based system, I […]