Linux

Using the Alpine Linux email client to access messages from any network

Sometimes when I’m traveling, I have trouble sending email from my devices that typically connect to my ISP at home via hardwire or WiFi. This is because some ISPs do not like outbound email to leave their network unless it is routed through their own email servers. But you need to have an account with the ISP in order to send outbound email through their servers.

This intentional blocking of outbound port 25 for email is usually aimed at preventing hijacked hosts from acting as spambots and sending email over the ISP’s network.

Read about how I circumvented that problem.

David Both
Read More
Linux Startup systemd

Replacing rc.local in systemd Linux systems

Missing rc.local for adding commands to run on startup?

The rc.local file was—and in some cases still is—the place for Linux sysadmins to put commands that need to be run at startup. Use of the rc.local file is not only deprecated but after a couple of hours worth of attempts, was not working in any event. This despite the fact that the systemd documentation mentions the use of a “generator” that generates systemd services from an rc.local file if one exists.

Here’s how to set up similar functionality with today’s systemd.

David Both
Read More
Linux Problem Solving

Problem solving strategies for SysAdmins

Solving complex problems is not a straightforward proposition.

I’ve participated in plenty of technical interviews with people who had passed many certification tests and who had fine resumes. I also participated in many interviews in which we were looking for Linux skills, but very few of those applicants had certifications. Very few of the Linux applicants were yet certified.

Few of the Windows certificate owners could reason their way through the scenarios we presented while a very large percentage of the Linux applicants were able to do so.

David Both
Read More
Linux System Administration

Managing devices in Linux

There are many interesting features of the Linux directory structure. In this article I cover some fascinating aspects of the /dev directory.

Device files are also known as device special files. Device files are employed to provide the operating system and users an interface to the devices that they represent. All Linux device files are located in the /dev directory, which is an integral part of the root (/) filesystem.

David Both
Read More
File Management Linux System Administration

Get started with Midnight Commander, a visual shell and file manager for Linux

Midnight Commander (MC) is a text-based Command Line Interface (CLI) program. It is particularly useful when a GUI is not available but can also be used as a primary file manager in a terminal session even when you are using a GUI. Midnight Commander can be used to interact with local and remote Linux computers using the CLI.

The man page for Midnight Commander calls it a visual shell because it’s capabilities are greater than the file manager we usually use it as. This article will provide you with enough information to get started using Midnight Commander as a file manager as well as its other capabilities.

David Both
Read More