SSL stands for Secure Sockets Layer and it an old implementation of a crytographic protocol. TLS, or Transport Layer Security, is a new one. They are both used to have privacy in the communications between different parties. They are used to secure email, web browsing, instant messaging, etc These protocols work in a complex way […]

A brief introduction to SSL/TLS certificates

How to install the ELK stack on CentOS 8
The ELK stack stands for Elasticsearch, Logstash and Kibana. These three pieces of software are very useful since each brings a powerful capability that in combination is just great to use. Elasticsearch is a search and analytics engine. Logstash can process data from multiple sources. Kibana allows to visualize data in a graphic manner. These […]

How to install Webmin on FreeBSD 12
Webmin is a fantastic tool for those willing to administer UNIX or unix-like systems through a GUI interface. While the CLI interface lets any user to interact with these kind of systems to the very core and extract all the juice, there are tasks where the graphical interface makes sense and its visual and quick […]

Nmap cheatsheet
Nmap is a discovery tool used in security circles but very useful for network administrators or sysadmins. One can get information about operating systems, open ports, running apps with quite good accuracy. It can even be used in substitution to vulnerability scanners such as Nessus or OpenVAS for not very large environments, or quick audits. […]

How to mitigate Spectre and Meltdown on a Lenovo T430s laptop with Ubuntu
As recently announced in a previous article I wanted to write a couple of guides on how to mitigate Spectre and Meltdown vulnerabilities in GNU/Linux and UNIX environments. It is always a good and I hope a standard practice to have your systems patched and if they aren’t for whatever the reason (that legacy thing […]

How to install Apache in FreeBSD with pkgng
The Apache Web Server is one of the most widely deployed web servers around the world. There are new and powerful alternatives you may have heard of, such as NGINX which seems to be the coolest thing around lately. There are meaningful differences between the two. Both are great but for example Apache has set […]

How to install Docker on Ubuntu 18.04
Operating System level virtualization is hitting hard now, as much as VM’s did just a few years ago. Docker is the popular framework for this matter, the new kid on the block so to speak. This is the hot spot now and if anyone wants to appear knowledgeable about system administration knowing this technology is […]

Linus on ZFS
Disclaimer: What you are about to read may contain inaccuracies. Feel free to discuss them somewhere else. This is also my opinion and as such it may change through time, maybe tomorrow, next month, next year, next decade or never. I do also make very few reviews (if any) of what I write here so […]

What is GNU/Linux?
To answer this question one must split it. Plus make other questions like: «What is a, so called, Linux distro?». It seems complex and it is in a way. But let´s explain GNU/Linux in simple terms. GNU stands for GNU is Not UNIX. So it´s clear is not UNIX but it´s related to it in […]

Linux VS open source UNIX
Linux is the mainstream UNIX-like platform of choice in the modern world. There are valid open source code base alternatives from which many businesses have benefited from. This is a different approach on both.
