Issue #222 / May 2019

Highlights:

Modern filesystems make it easy to take a snapshot -- a precise copy of your data at a moment in time. This month we review some leading Linux snapshot tools.

Also in this issue:

• Redundant Internet Links -- With a little help from OpenWrt, you can support two Internet uplinks from your little home router.
• tmate -- access a remote shell session.

Stop by MakerSpace to build your own WiFi-controlled airboat. Check out LinuxVoice for a helpful tutorial on Bash test conditions and a study of two useful outline tools: CherryTree and Piggydb.

SERVICE: Welcome

Big Deal

When I started this job 15 years ago, Debian was a really big deal. The whole Linux community paid attention to Debian elections, and this magazine even had a regular monthly column devoted to Debian affairs. It would not be an exaggeration to reveal that I even knew a guy who had the Debian spiral tattooed on his neck.

SERVICE: This Month's DVD

This month's DVD includes CentOS 7.6 (1810) and Kubuntu 18.10 "Cosmic Cuttlefish."

NEWS: NEWS

In the news: VMware rolls out essential PKS; Linux 5.0 is here; Kali Linux 2019.1 is available; Linux Foundation releases a new draft of OpenChain specification; hackers start exploiting a Drupal bug;  LibreOffice is vulnerable to a remote code execution flaw; and an early warning system for seismic events.

NEWS: Kernel News

Chronicler Zack Brown reports on printk() wrangling, persistent memory as a generalized resource, making Kernel headers available on running systems, and Kernel licensing Hell. 

NEWS: Snapshot Tools

Choosing a storage snapshot tool

Experts agree that you should keep a copy of your data, but restoring from incremental backups takes time and sometimes doesn't work as expected. Alternatively, you can capture your data in a snapshot. Read on for a review of some leading Linux snapshot tools.

REVIEWS: KDE Plasma 5.14

The best Plasma ever

KDE Plasma 5.14 brings some highly visible improvements for KDE users.

IN-DEPTH: OpenWrt with Mwan3

Redundant Internet connections on consumer hardware with OpenWrt and Mwan3

Redundant Internet uplinks are standard on big corporate networks, but they are still the exception for the home and small-office sector. If you're ready to experiment, you can set up redundant Internet connections on your own home router with OpenWrt and the powerful Mwan3 extension.

IN-DEPTH: New Commands for Old Purposes

Simplifying and improving standard commands

As the standard core Linux commands have become more complex due to revisions, new commands have risen to take their place. Bruce looks at seven of these modern commands, plus a terminal emulator.

IN-DEPTH: The sys admin's daily grind: Adminer

At the First Click

Sys admin columnist Charly freely admits that he doesn't like SQL and phpMyAdmin any more than he does COBOL. Instead, meet his new best friend; the slim, attractive database tool known as Adminer.

IN-DEPTH: Programming Snapshot – Gimp

Gimp image optimization with Python plugins

Performing the same Gimp image processing steps again and again is tiresome and error prone. Mike Schilli assigns this task to a Python script via a home grown new menu entry.

IN-DEPTH: tmate

Emergency shell access with tmate

Tmate lets you access the shell session of a remote computer – even through a router.

IN-DEPTH: LibreOffice PDFs

PDF types in LibreOffice

With LibreOffice, you can customize the way you export PDFs.

: MicroPython and ESP8266

MicroPython and ESP8266 Airboat

An airboat project uses a standalone WiFi web server for remote control.

NEWS: Decisions, Decisions

Choosing the right board

When it comes to open hardware projects, the choice of an Arduino or a Raspberry Pi board can determine success or failure. Read on for guidance in selecting the best board for your specific needs.

LINUX VOICE: Introduction

This month in Linux Voice.

LINUX VOICE: maddog's Doghouse

A promise of open hardware

After 25 years of waiting for open hardware, Maddog predicts the era of closed, proprietary chips as the only option is drawing to an end.

LINUX VOICE: CherryTree and Piggydb

Comparing the CherryTree and Piggydb outline editors

Organize your thoughts with the CherryTree desktop app and an innovative web application called Piggydb.

LINUX VOICE: Filesystem Tools

Identify mounted filesystems

Tools like mount and findmnt reveal which partitions and filesystems are mounted on your computer.

LINUX VOICE: FOSSPicks

This month Graham looks at Neuronify, Undervolt GUI, Entropy Piano Tuner, Gnome Internet Radio Locator, Hatari, and more!

LINUX VOICE: Decision Making Scripts

Shell test conditions and exit codes

The Bash shell uses different criteria to make decisions. Learn how to teach your shell scripts to make the right choice.

LINUX VOICE: Designing your own stuff with OpenSCAD

3D Designer

Ah! What a joy your first 3D printer … but once you have printed your first benchy, where do you go from there? To building your own pieces, of course!