today's howtos

posted by Roy Schestowitz on Aug 05, 2023

• Try the Last Internet Kermit Server

  What is this mysterious protocol? Who uses it and what is its story?

  This story is a winding one, beginning in 1981. Kermit is, to the best of my knowledge, the oldest actively-maintained software package with an original developer still participating. It is also a scripting language, an Internet server, a (scriptable!) SSH client, and a file transfer protocol.

  And my first use of it was talking to my HP-48GX calculator over a 9600bps serial link. Yes, that calculator had a Kermit server built in.

  But let’s back up and talk about serial ports and Modems.

• On Linux, NFS v4 mounts are a different filesystem type than NFS (v3) mounts

  For more or less historical reasons, we currently use NFS v3 to mount filesystems from our fileservers. We're likely going to (slowly) move over to NFS v4 (after successful experiments), so I've been working on various preparations for that, such as making sure our automounter system doesn't specifically force NFS v3 but instead leaves it up to the system to pick a version. In the process of this, I've discovered a surprise.

  On Linux, NFS v4 mounts have the filesystem type 'nfs4', not 'nfs'; the 'nfs' filesystem type is for NFS v3 (and NFS v2, if you're using that, which you probably shouldn't be). Linux's normal 'mount' program will accept 'mount -t nfs ...' and do a NFS v4 mount if the server supports it, but listing mounts with 'mount -t nfs' will only list NFS v3 ones, and the actual filesystem type in /proc/mounts (aka /proc/self/mounts) and other things is 'nfs4'.

• Try installing from source first

  A good reason to use package managers when installing software is that it normally just works. And while that's a very compelling reason, I still think developers should first try installing software from source when possible. The two main advantages of installing from source are: learning and control. Control over how the package is built, what's included, where it goes, how it's managed and the flexibility to apply patches and versions possibly not available in your package manager.

  Now, I'll be quick to admit that you probably shouldn't spend a huge amount of time trying to install something from source. For many packages the best case scenario is a complicated process requiring specific build tools and dependencies with their own complications. The worst case scenario is poor or lacking documentation and no idea how to even get started.

  But, you can try.

• Prometheus scrape failures can cause alerts to be 'resolved'

  Prometheus expressions act as filters, or to put it another way, we're doing set operations. What an alert rule expression really yields is some number of individual time series, each with its own set of labels. Each time series will become an alert (with its labels taken from the time series), either a pending alert or a firing alert depending on whether or not the alert rule has a 'for:' (see my entry on delays and timings for alerts). As long as the alert rule expression continues to produce that time series, the associated alert will stay active. When the alert rule expression stops producing that time series, the associated alert goes away (unless you've set 'keep_firing_for' on it).

• Getting started with Fail2Ban on Linux

  I want to show you how to get started with Fail2Ban to keep your Linux servers more secure. For this blog post, I've used Ubuntu 22.04 LTS as a reference and will use it to secure my SSH service with iptables as the firewall. I assume that you already installed it on your system.

• How to Install Nextcloud Desktop Client on Fedora 38/37 Linux

  In the rapidly evolving realm of cloud computing, the Nextcloud Desktop application stands as a beacon for those seeking a harmonized approach to data management and synchronization. This guide aims to walk readers through the meticulous steps required to install the Nextcloud Desktop client, employing Fedora’s esteemed RPM repository.

• How To Install Gitea on Fedora 38

  In this tutorial, we will show you how to install Gitea on Fedora 38. For those of you who didn’t know, Gitea is a lightweight, self-hosted Git service that allows teams and individuals to collaborate efficiently and manage version control for their software projects.

• How to Install Lutris on Fedora 38/37 Linux

  In today’s era of gaming, diverse platforms and an assortment of game titles have made managing one’s gaming library a crucial aspect for enthusiasts. Enter Lutris, a comprehensive game manager tailored for Linux. This guide will demonstrate how to install Lutris on Fedora Linux utilizing Fedora’s RPM repository.

• How To Install Git Fedora 38

  In this tutorial, we will show you how to install Git on Fedora 38. For those of you who didn’t know, Git revolutionized version control systems with its distributed nature, allowing developers to work offline and collaboratively on the same project.

• Linux Head Command: View Top of Files & Command Output

  In Linux, the head command is a commonly used command-line utility that allows you to view the top portion of a large file or the output of the command.

• Install OpenNMS Network Monitoring system on Ubuntu

  OpenNMS, also known as “Open Network Management System”, is a free, open-source, and powerful network management and network monitoring solution. An enterprise network management system monitors and manages various services and devices from a central location. OpenNMS can be installed on Windows and Linux-based operating systems.

• ps Command in Linux with Examples

  The ps command in Linux stands at the forefront of powerful command-line utilities, offering critical insights for system administration and monitoring. Short for “process status”, it delivers detailed information about the currently running processes, including their process identification numbers (PIDs).

• How To Install Grafana on Fedora 38

  In this tutorial, we will show you how to install Grafana on Fedora 38. In today’s data-driven world, the ability to visualize and analyze data effectively is paramount. Grafana, an open-source tool, empowers users to create stunning visualizations and monitor systems with ease.

• How to Install Java on Debian 12 (Bookworm)

  Learn how to easily install Java on Debian 12 (Bookworm) with our step-by-step guide. Enhance your system for powerful Java applications!

• How to install Discord on Debian 12 "Bookworm"

  Discord is one of the most popular chatting software that gamers use. Even though Discord was created mainly for gamers, nowadays many companies use Discord for different purposes.

  There are several different methods to install Discord on Debian 12.

• How to Install and Use Paru to manage AUR packages on Arch Linux

  Paru is a new AUR helper that you can use to install and download packages from AUR repository on Arch Linux.

  Paru is based off Yay. However, the difference is that, Paru is written in Rust, while Yay is written in go.

• rmdir Command in Linux with Examples

  The Linux operating system is admired for its robust command-line utilities, offering users profound flexibility and control. One such utility is the rmdir command. The rmdir command, an abbreviation for “remove directory”, is an essential tool for users aiming to maintain an organized filesystem.

• How To Install Laravel on Debian 12

  In this tutorial, we will show you how to install Laravel on Debian 12. For those of you who didn’t know, Laravel has emerged as one of the leading PHP frameworks for web development, offering an elegant and efficient approach to building web applications.

• cd Command in Linux with Examples

  In Linux, the “cd command” is pivotal for navigating the open-source operating system’s vast filesystem. This seemingly simple command, standing for “change directory,” is a cornerstone of user navigation and file management, showcasing the depth and power of Linux’s command-line utilities.

• sed Command in Linux with Examples

  Linux, a versatile open-source operating system, offers various command-line utilities for various tasks. The sed command, standing for Stream Editor, holds a significant place among these utilities. It’s specifically tailored for parsing and transforming text in a data stream or file.

• How to Install Discord on Linux Mint 21/20

  Discord is a popular communication platform designed for gamers, but it has since become widely used for various purposes, including business, education, and personal communication.

• How to Install GIT on Linux Mint 21/20

  Git is an incredibly powerful and popular version control system (VCS) developers worldwide use to manage and track changes in their codebases. It was created by Linus Torvalds, the same person behind the Linux operating system, in 2005.

• How to Install SeaMonkey on Linux Mint 21/20

  If you’re a Linux Mint user seeking an alternative to mainstream Internet suites, SeaMonkey could be your next destination. This integrated Internet application suite might not get the same buzz as Google Chrome or Mozilla Firefox, but it has a unique charm that’s all its own.

• Creating and Extracting Archives with the tar Command in Linux

  How to Use tar Command in Linux Objective The objective of this article is to explain various steps of creating backup data...

• Creating Directories in Linux: A Beginner’s Guide to the mkdir Command

  If you are looking at how to make a directory in Linux then you are at the right place...

• How to use Linux Mint without installing on a Mac – Linux Mint 21.2 edition

  In a previous tutorial I explained how to create a Linux bootable USB drive in macOS.