Well, it’s been a while since my last post and I think it’s about time I started posting some new stuff here. During all these months I spent my free time οn various things. As far as tech is concerned I mostly spent time on Linux servers and a little bit on software development. Digging into the Linux Desktop is not a top priority for me any more since I only use it on secondary desktop boxes or virtual machines, so there isn’t much to write about it. So, I’ll be getting my notes together and I’ll try to post some cool and interesting guides in the next months.

There has been much controversy about Copyright and file-sharing on the internet during the last decade. Admittedly, the All Rights Reserved statement is incompatible with the nature of communications in the Digital Age and thus a new more flexible content and media licensing scheme is required. A permission system would be the natural solution to the All-Rights-Reserved problem (it could even be extended to Patents, but this is outside the scope of this post). Such a permission system is imposed by Free Software licenses, Creative Commons licenses and others. Although it’s not perfect, it does provide an acceptable and realistic solution for content, media and software publishing in the Digital Era.
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Software has become part of our lives. Businesses, homes and even individuals more and more rely on software to meet their goals and serve their needs. Recently, I had tried to have a discussion with people who are active in the FLOSS ecosystem about if and how the development process of free software could be improved in order to increase its quality and efficiency. As usual, the conservative minds within the community did not let the discussion get far. This was not the first time nor the first place I tried to start a discussion like that. Nevertheless, the outcome has always been the same.
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There are several ways to improve the performance of a web site. One of them is HTTP compression. Moreover, compressing the web server responses can save tons of bandwidth without adding any significant amount of extra CPU load on the server. Two of the most common compression algorithms used in HTTP are gzip and deflate. An article containing step-by-step instructions on how to configure Apache to compress web server responses using mod_deflate had been published on G-Loaded a long time ago. This post is about the web browser support for the gzip, deflate and raw deflate compression algorithms. The following page contains the results of several compression tests run by various modern and older web browsers. In case you had been looking for such information, that’s a good place to start.

I tested the website using the default browser of a smartphone and I realized that it is needed to improve the theme to make the content easier to read on mobile devices. If you think such a task is easy, you’re way outline! From a quick web search I noticed that there are many things to take into consideration before making any changes. I’m currently gathering information that will help me decide what would be the best way to serve two versions of the content, one suitable for mobile devices (smartphones and tablets) and one of PCs (desktops, laptops). If you’ve gone through this procedure and care to provide some insight, feel free. read more… »

From the time I had set up my first server at home over a decade ago, I’ve performed numerous operating system upgrades. Usually, it used to take me several hours – if not days – to complete each upgrade and make sure that everything would work as expected. During all these years, I’ve been working hard whenever time permitted it in order to make several pieces of software work flawlessly together requiring the least possible time for manual maintenance. Despite the deployment of my services having reached a high level of automation, I recently spent almost a whole day upgrading CentOS in one of my remote boxes.
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It’s been a while since WordPress implemented revisions for posts and pages. Being able to revert a post or page to a previous state is a useful feature. However, I recently realized that WP creates a revision of the content every time it is saved, but there is no upper limit for the number of stored revisions. So, if you save your work quite often, it is very possible that the WordPress database is filled with numerous revisions of the content, which make the database grow in size quite aggressively. After thinking about it for a while, I realized that all those revisions are pretty useless to me. All I really care about is having a couple of recent revisions of each post or page available, so as to be able to get an idea of my recent changes.
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By default, when the user installs software through the RPM Package Manager or through YUM, usually, the software’s configuration files included in the RPM do not replace the existing configuration files on the filesystem, but, if they differ from those that currently exist, they are saved with the rpmnew extension. In case the rpm is already installed and is the latest version, the quickest way to get the original configuration file back is to uninstall and install the package again. Today, while on CentOS 6.2, I needed to restore the original /etc/sysctl.conf file, which is part of the initscripts package. In this case, uninstalling initscripts was out of the question as it would also remove half of the installed packages due to dependencies. So, I grabbed the chance to figure out and document what would be the quickest and easiest way to restore /etc/sysctl.conf, excluding downloading the package itself and extract the RPM contents. Fortunately, as soon as I opened yum’s man page and having spotted the new reinstall command, the solution was quite obvious.
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I cannot overstate how disappointed I am after having a discussion with people who tend to partially mix the various declarations of Rights and the Law in order to make a point valid enough to justify their actions. I am not really the one to tell whether such behavior derives from competence or incompetence. What i do know is that I will never again join any discussion which, at least, is not based on common sense. Ever.

It is widely known that, if virtual hosts in Apache (httpd) are configured to permit vhost administrators override specific configuration options at the directory level using htaccess files, the web server consumes valuable time in order to check whether an htaccess file exists in every directory included in the requested path and parse it. On the other hand, many popular web applications utilize htaccess files, especially those residing in the DocumentRoot, in order to implement pretty URLs or HTTP redirections, which is extremely convenient since the virtual host owner does not have to edit httpd’s configuration directly. So, I had the idea to include the htaccess file of the DocumentRoot directory on the filesystem into the virtual host’s configuration.
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