cron.weekly issue #30: systemd, GitLab, Jenkins, Ansible, Nix, Atop and many more!

cron.weekly is a newsletter about Linux, open source & webdevelopment. Want to get it in your inbox every Sunday? Subscribe below!

I respect your privacy and you won't get spam. Ever. Just a weekly-ish newsletter about Linux and open source.

Want to help support this blog? Try out Oh Dear, the best all-in-one monitoring tool for your entire website, co-founded by me (the guy that wrote this blogpost). Start with a 10-day trial, no strings attached.

We offer uptime monitoring, SSL checks, broken links checking, performance & cronjob monitoring, branded status pages & so much more. Try us out today!

Image of Mattias Geniar

Mattias Geniar, May 29, 2016

Follow me on Twitter as @mattiasgeniar

Welcome to cron.weekly issue #30 for Sunday, May 29th, 2016.

There’s some systemd drama, a lot of tutorials and guides and a couple of interesting new project releases. All in all, it’s been a good week for open source.

If you have any feedback – both good or bad – let me know, I’m always looking for ideas to improve the newsletter.


Google beats Oracle—Android makes “fair use” of Java APIs

A lawsuit that lasted for over 6 years and eventually ruled in favour of Google: the use of the Java API’s in the Android OS is considered ‘fair use’. This could be a precedent for future cases where intellectual property is discussed.

Another controversial systemd release: v230 

This is one is bound to get a lot of attention: the newest systemd released was tagged as v230 and next to a lot of stability improvements, it also has a big change: systemd-logind will now by default terminate user processes […] when the user

logs out. There’s already a Debian bugreport. The commit can be found here.

Python 2.7 countdown

It’ll still take 3 years before Python 2.7 is end of life, but this new site has a big countdown and some links to make sure you migrate to Python 3 in time.

Tools & Projects

Introducing Blue Ocean: a new user experience for Jenkins

A while new user interface for Jenkins is being made codenamed ‘Blue Ocean’. A radical rethinking of visualising the data flow within a Jenkins pipeline – it looks like a very big improvement, too!

GitLab Container Registry

The latest release of GitLab, the self-hosted git repository like Github or Bitbucket, also has a container registry now: this means it’s much easier to have containers be created as a result of a git commit and be registered in the container registry for use.

Ansible 2.1 released

This release of Ansible mostly focusses on network automation with support for Cisco, Juniper, Arista, … Other noteworthy items are better Docker support, Windows support is out of beta and Azure Cloud automation is now possible with Ansible.

Roundcube Webmail 1.2.0 released

The 2 biggest features in this new webmail release are: support for PGP encryption and support for PHP 7.

Mattermost 3.0 released

Mattermost is an open source, self-hosted Slack-alternative and the 3.0 release offers some goodies: multi-team accounts, iOS/Android app updates, full width views and Ruby API’s.

Guides & Tutorials

Use atop for Linux server performance analysis

A nice overview of the benefits of ‘atop’ vs ‘top’ for performance analysis. Its biggest benefit is that it runs as a daemon, collecting system metrics for you to review later.

Containers 101: Linux containers and Docker explained

A brief introduction to lightweight, portable, flexible Docker containers and why developers love them.

Puppet Server: advanced memory debugging

A really nice read if you have a Puppet master running: lots of in-depth info on configuration parameters, getting metrics, different limits in Puppet master and quite a bit of Ruby debugging at work.

Nix as OS X Package Manager

Nix is a rather new but interesting package manager, which provides atomic upgrades and rollbacks, side-by-side installation of multiple versions of a package, multi-user package management and easy setup of build environments. This post describes how to use Nix as a package manager on your OS.

MongoDB 3.2: elections just got better!

MongoDB 3.2 revamped its election protocol for increased stability, in this blogpost, the Percona team reviews MongoDB 3.2 elections and how they work, as well as what is really new and different in the election protocol.

Xen exploitation part 1: XSA-105, from nobody to root

I love security write-ups like these: this post explains how to abuse the Xen vulnerability XSA-105 to get a root account from a non-privileged user on a Xen guest VM.

Who Needs Git When You Got ZFS?

This post introduces the concepts of ZFS and a lot of practical commands to use ZFS at the command line. The main goal is to use the snapshots and repositories in ZFS to create versioned data-points that you can fallback to, much like a git commit.

How to Move from Amazon RDS to dedicated PostgreSQL server

This is a very practical post on how to migrate a PostgreSQL server from one machine to another. The post describes it as “from AWS”, but it applies to all kinds of PostgreSQL installations.

Building RPMs for fun and profit

A good step-by-step guide that explains the SPEC files and how to go and create your own RPM files.

TOTP SSH port fluxing

You know those 2 factor authentication apps that generate a random number every 10 seconds to authenticate you with? Well, this guy hooked it up to its SSH port: the SSH port changes every couple of seconds, and a 2FA app tells him which port to use.

ssh -R (reverse tunnel) man page hell

If you’ve ever set up a reverse tunnel in SSH, you know the manpages aren’t too clear on this. This post has a nice diagram that shows how reverse tunnels work and how the CLI arguments should be used.


Laracon EU 2016

This conference takes place on August 23rd and 24th in Amsterdam, Netherlands. It revolves around PHP and Laravel (a popular PHP framework). I’ll be giving a talk on Varnish for PHP developers. If you’re there, come say hi!

Want to subscribe to the cron.weekly newsletter?

I write a weekly-ish newsletter on Linux, open source & webdevelopment called cron.weekly.

It features the latest news, guides & tutorials and new open source projects. You can sign up via email below.

No spam. Just some good, practical Linux & open source content.