Setting the firewall up is a mandatory task on any computer facing the internet. This is a simple, straightforward how to article on how to setup a box with an easy firewall configuration on FreeBSD. If you find the articles in Adminbyaccident.com useful to you, please consider making a donation. Use this link to get […]

How to setup a simple firewall in FreeBSD using IPFW

How to mitigate Spectre and Meltdown on an HP Proliant server with FreeBSD
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 OSSEC agents on Windows
On a recent post I published about how to install an OSSEC server on Ubuntu I explained how this solution can help secure an infrastructure by deploying agents which report back to a central server. This is the second part of this server-client story. On this guide you will read about setting up agents and […]

How to manage site visitors based on IP Geolocation
Whenever someone publishes a website on the internet, most of the times, their intention is that site to be seen around the globe. However, as a site administrator you may want to divert users from one country to visit some specific version of that site, maybe because of the visitor’s language. Other times, less often […]

How to replace a disk on a ZFS mirror pool
It’s happened to me, it’s happened to you, it’s happened more than one million times and it will still happen in the future. You run out of disk space or a disk fails. Nowadays you are using ZFS, and instead of having a fancy RAIDZ, because you still don’t need it, you are using a […]

Nessus vulnerability scanner
Nessus is a very well known vulnerability scanner used by many large and small companies to assess their systems and correct the issues found in them. Cybersecurity teams and specially auditors, make heavy use of tools like this in order to follow up the state of infrastructure and environments. Having a tool like this saves […]

A brief introduction to Regular Expressions
A regular expression is a set of characters, a string of characters if you will, that specify a pattern. Ever used the grep command? It makes use of them. The ‘grep’ command is very handful when one needs to look for certain things inside a text file, or looking for some specific pattern from another […]

How to manually update Letsencrypt certificates on FreeBSD
Update 05-2020: If anyone is interested on the automatic process you can read my tutorial on DigitalOcean about the topic. On this guide we will manually update our Letsencrypt certificate on FreeBSD for a single website. It is a simple operation that can be automated as a cron job, but seeing it is always informative […]

How to configure TLS 1.2 on UNIX or GNU/Linux
This is an article willing to help and point out a few useful resources for those using Apache HTTP or NGINX web servers that are still using the deprecated SSLv3, TLS 1.0 and/or TLS 1.1 verions. If you find the articles in Adminbyaccident.com useful to you, please consider making a donation. Use this link to […]

How to connect a FreeBSD box to the internet through an Android device via an USB port
FreeBSD is known to be very suitable for computer servers, from Netflix streaming to Whatsapp messaging as powerful examples. Some also use FreeBSD as a workstation OS. I am one of those using BSD on both camps, although I also use some GNU/Linux boxes for ‘trivial’ purposes. In modern times having an internet connection seems […]
