cron.weekly issue #75: Shoop, journal-triggerd, Bash, SSH, iostat, hadoop, MySQL, videos & more

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Mattias Geniar, April 09, 2017

Follow me on Twitter as @mattiasgeniar

Welcome to _cron.weekly _issue #75 for Sunday, April 9th, 2017.

A packed issue again, which shouldn’t surprise you anymore I guess – it’s nearly always a packed issue. 🙂

I’ll be traveling next week and I might need your help for next week’s issue: if you spot interesting links or articles, feel free to send them my way via e-mail or on the @CronWeekly twitter account.

Happy Sunday!


And then I saw the Password in the Stack Trace

This post is a good reminder that error messages can contain sensitive information. If you run (web) applications in production, make sure to turn off the displaying of errors and stacktraces.

CAA checking becomes mandatory for SSL/TLS certificates

In September 2017, Certificate Authorities are obligated to check for the “CAA” DNS record to verify if they’re allowed to issue certificates for a particular domain. If you care about your TLS certificates, you might want to implement CAA for your domains.

Ubuntu Unity is dead: Desktop will switch back to GNOME next year

I don’t usually care for Linux Desktop news, but this struck me as big news; Ubuntu has been pushing Unity for the last few years, but has decided to revert back to the GNOME desktop.

Spotify’s Love/Hate Relationship with DNS

An interesting read on Spotify’s use of DNS, their service discovery, automation, etc. It also includes an interesting mechanisme for doing song lookups based entirely on DNS, no other payload required.

Tools & Projects

Datadog: all your infrastructure, in one place

Track & alert on the health and performance of every server, container, and app in any environment, with Datadog. Sign up for a free 14-day trial. (Sponsored)


Shoop is a high-speed encrypted file transfer tool reminiscent of scp. It uses SSH to bootstrap authentication and encryption, then uses UDP instead of TCP. Think of it as “scp meets mosh“.

CentOS 6.9

A little over a week after Red Hat’s 6.9 release, CentOS follows: you can now upgrade your CentOS 6.x boxes to the latest 6.9 release.

Packer 1.0

Packer is a tool for building images for cloud platforms, virtual machines, containers, and more from a single source configuration.


Helios is a Docker orchestration platform for deploying and managing containers across an entire fleet of servers. Helios provides a HTTP API as well as a command-line client to interact with servers running your containers.


journal-triggerd is a small daemon that runs in the background, listening to systemd’s journal, and will run “triggers” (i.e. exec a command line) when certain messages are added.


Magnetico is the first autonomous (self-hosted) BitTorrent DHT search engine suite that is designed for end-users.


A beautiful way to manage your Hashicorp Vault as a webapplication.


Heketi provides a RESTful management interface which can be used to manage the life cycle of GlusterFS volumes.

Guides & Tutorials

Understanding Bash History

There’s quite a lot you can do to tweak the output and content of the history command on a Unix box, this post explains the possible configuration parameters.

SSH and terminal background

A cool hack for iTerm to change your Terminal’s background window if you SSH into certain machines, to make it more visual which host you’re currently on.

The Linux kernel user’s and administrator’s guide

Lots of links to follow-up on regarding reporting kernel bugs, bisecting a bug, the panic logger, …

Linux reverse engineering 101

A collection of resources for linux reverse engineering.

Better git configuration

Lots of links on configuring & using git, from a better/alternative _`git log` _to colored output, aliases, merging, …

Performance Monitoring with Vmstat and Iostat

vmstat, sar and iostat commands are the collection of package included in sysstat – the system monitoring tools. The iostat generates reports of CPU & all device statistics.

Fun at the UNIX Terminal Part 1

This post explains how to use ROT13 “encryption” (character substitution) with the tr tool, the fortune command, say & cowsay and plenty more tools. The goal is mostly “fun”, not so much productivity or work.

How To Learn Hadoop For Free

This post contains lots of links and articles to learn about the Hadoop ecosystem.

How to Fix a Lagging MySQL Replication

If you’ve ever run MySQL replication, you will have suffered replication lag at one point, where your slave(s) fail to keep up with your master. This post explains parallel replication & the different types & how innoDB flushing configurations work.

Tools that make my life easier to work with kubernetes

This is a good collection of tools, autocompletion configurations, … for anyone working with Kubernetes clusters.

Manually Throttle the Bandwidth of a Linux Network Interface

An introduction to the “tc” tool for bandwidth shaping.


TROOPERS conference 2017

Nearly all talks of the TROOPERS conference have been released. Lots of security related talks on web applications, linux, networking, windows, iot, …

CloudNativeCon + KubeCon 2017

This conference revolved around everything cloud; Kubernetes, storage clusters, containers, lifecycle management, … lots of interesting talks in this list.

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