In some of my previous posts, I discussed about using PHP as part of LAMP for web application development. Well, if you haven’t noticed it already, when I said PHP, I was talking about PHP version 5 or 5.x. However, now I’m going to specifically talk about PHP7 and what new features it brings to the table. PHP History PHP5, which is the most popular and most widely used PHP version, was introduced in 2004 and immediately after its launch, development of…
There is a term called “Git” in IT field, which may not be much familiar to most people despite being one of the most useful and handy tools in the industry. So, in this post, I’m going to cover the introduction and getting started guide for Git so that more people will be able to understand it and leverage its benefits. What is Git? Basically, Git is a distributed version control system. So, what is version control system and why should…
Hello and welcome! In my previous post on LAMP web server, I discussed about its installation and configuration inside CentOS environment. Today, I’m writing on how to setup SSL certificate in our website and other security related configurations as well. Installing SSL Certificate First of all, let’s install mod_ssl package from MOD Security. It’s done in CentOS as follows: Then, let’s create a directory where we’ll keep our SSL certificates. Now, let’s generate self-signed certificate for our web server. Here, openssl is…
Welcome back! In this post, let’s talk about tightening our Antispam or Spamassassin in Zimbra. In real-time, there may be a serious reason for filtering and blocking mails based on subject that contain certain structures or words. Here are the steps to achieve this objective in Zimbra 8.5 and later. 1) Create a policy file inside /opt/zimbra/data/spamassassin/rules/ as root user e.g. Here, SUB_ATTACHMENT is a rule that filters the mail header based on the regular expression match of Subject. The describe…
Hello there! In this post, I’m going to write about how to enable authentication in Zimbra CBPolicyd Webui. If you use Zimbra but haven’t yet used CBPolicyd, I recommend you to see me previous post where I discussed about installation and use of CBPolicyd for managing mail related rules or restrictions in Zimbra. Until now, we don’t have any kind of authentication mechanism to protect our CBPolicyd’s web panel. So, let’s go ahead and setup an authentication method for our…
Hello! In this post, I’m going to talk about how to configure a Zimbra server to restrict certain users from sending or receiving mails from external domains. In order to achieve this objective, Zimbra provides two alternatives: one using CBPolicyd (web based) and another using MTA restrictions (cli based). Here I’m covering both methods. First, let’s have a look at CBPolicyd. Note: The methods mentioned here are tested successfully in ZCS 8.5 and ZCS 8.6. I cannot confirm its validity…
Welcome! In this post, I’m once again going to discuss about Zimbra Collaboration Suite. This is about an incident that I recently came across, in which some of the mail distribution lists of one of our clients got automatically removed from the system. On doing some research, I learned that this type of issue was faced in past versions of ZCS, and had been resolved long ago. However, in this case, our client had the latest ZCS version of the…
Hello and welcome back. Today, let’s learn about Cisco’s Unified Computing Systems (UCS) technology. If you haven’t heard of Cisco UCS before, this might be a good opportunity for you to keep yourself updated with the recent developments in IT industry. Basically, UCS is an aggregation of computing systems, virtualization, switching fabric and centralized management for deploying and running the entire data center. As part of UCS, Cisco provides rack-mount servers and blade servers for computing and Nexus/MDS switches for fabric switching….
Hello! Today, let’s install and configure a web server (Linux + Apache + MySQL + PHP = LAMP) in CentOS7 platform. I think this subject can be very helpful to web developers, students and system administrators. Without any adieu, let’s get started with the installation and configuration. Installation of CentOS 7 I’ve already written blogs on installation and initial configuration of CentOS 7 operating system in my previous posts. You can refer to these blog posts: Creating VM in VMware…
Welcome back! In this post, I’m getting into somehow different topic than my usual ones. Here, the subject matter that I’m diving into is storage traffic switching with Cisco MDS series switches. If you’re new to this subject, here are some basic introductions: First, Storage Area Network (SAN) is much like the well-known Local Area Network (LAN), with an exception that it carries storage traffic or SCSI commands among storage devices (target) and servers/clients (initiator). There are mainly two technologies that…