Setup Nagios Alerts to Monitor SSL Certificate Expiry in Java Key Store
May 14, 2022
The background Nagios is a monitoring tool1 for systems, networks, and infrastructure. The expected outcome was to add a Nagios alert for SSL Certificates stored in a Java Key Store file. Since the Nagios server was already set up and functioning, we’ll cover only for setting up the alert. The procedure Considering security and efficiency, it was decided to set up a cron triggered script to read the certificate expiry dates, write them to a location accessible by the Nagios Remote Plugin Executer (NRPE)2 agent.…
Updating VirtualBox on Ubuntu
Dec 01, 2021
How was it installed? The official apt repositories are known to have old (read thoroughly tested and stable) versions for some software packages. In that light, VirtualBox was installed through the latest stable .deb installer downloaded from the official website, with the version number at the time being 6.1.28-147628. When the new stable version 6.1.30-148432 became available, following are the steps that were followed to set it up. The Process First, we need to obtain a copy of the .…
Installing Gnome Shell Extensions Manually on Ubuntu
Nov 30, 2021
The Background The usual method to install Gnome extensions on Ubuntu is using a browser with the relevant browser extension installed among other requirements. However, as in almost all things involving Linux, this method is not necessarily the only way toward accomplishing the same. What follows are the steps that may be followed to manually download and install the extensions without browser integration. The Procedure We can get started by navigating to the Gnome Extensions webpage1, finding the extension we need installed, and downloading the extension package matching our Gnome shell version2.…
Setting Up an OpenVPN Server on CentOS
Nov 26, 2021
The Background Recently I’ve set up an OpenVPN (Community Edition 2.4.11) server on a CentOS 7 box. While there were multiple1 resources2 that3 helped4 immensely in getting the task done, below is the process that was actually followed. Configuring EasyRSA and Generating the Server Keys Once we have a CentOS 7 box up and running, we can start by enabling the EPEL repository and optional extras. yum install https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm subscription-manager repos --enable "rhel--optional-rpms" --enable "rhel--extras-rpms" --enable "rhel-ha-for-rhel-*-server-rpms" Then, we can install openvpn and easy-rsa5 as below.…
Adding a Program to Gnome Dock in Ubuntu
Nov 14, 2021
The backgroud I recently installed Ubuntu 20.04 LTS on a machine where I needed a solid and friendly OS1. I also wanted to install a couple programs including Lite XL2 and VS Code3 among others, and decided to use the pre-built binaries and setup them in a portable manner. For VS code, extracting the gzipped tar and creating an empty ‘data’ directory inside the extracted directory is the way to go.…
Resize Virtual Disk Image and Expand Linux LVM
May 01, 2020
If you are like me and create virtual machines with only a reasonable virtual disk size to start with (because you can always expand them in the future, right?), it is very much possible you encountering a situation where you want to increase the virtual disk size. And if you run Fedora like me, it is also possible you suddenly finding yourself looking for a way to expand a LVM partition to utilize the gained space once the VDI size is increased.…