TurnKey Linux Virtual Appliance Library

Security update regenerates stale SSH ECDSA host key

Peter Lieven from KAMP.de discovered a problem with TurnKey 13.0 where the OpenSSH ECDSA key is not regenerated on firstboot like the RSA and DSA host keys.

We've issued a signed hotpatch to TurnKey Core 13.0 that regenerates the ECDSA SSH host key. TurnKey deployments that have not disabled automatic security updates (it's on by default) will have their ECDSA SSH host key regenerated automatically within the next 24 hours.

configuring libresolv to timeout DNS queries to unreachable nameservers more quickly when offline

When I go offline I pull my network cable. This causes DNS queries to take forever to resolve. Actually 40 seconds but it feels like forever.

Smart cache expiration with Drupal Rules

I've been exploring Drupal Rules some more since last week.

We were already using it before to automate the various repetitive tasks involved in creating a new appliance (e.g., creating aliases for the feeds).

Intelligent caching

Now we're also using Rules in conjuction with the Cache Actions module to expire the cache page intelligently so that adding or removing published content expires related page caches immediately.

A practical intelligence amplification hack that really works: how to use your phone's TTS engine to give your brain a boost

The future is already here — it's just not very evenly distributed. 

- William Gibson

Today I decided it was time I shared a unique, literally mind bending experience I've been having. If I could only get one idea out into the wider world this would be it. It's the best piece of technology advice I have to give.

Try it and it could change your life. Tell your friends and we might change the world. It's changed mine more than any other technological innovation since I got my first modem back in 1993 and discovered the Internet a year later.

A practical brain machine interface you can use right now

Back in the mid 1990s, when I was  teenager I remember spending a lot of time speculating whether the technological singularity Vernor Vinge predicted would be driven by human IA (Intelligence Amplification), non-human AI (Artificial Intelligence) or both.

As a lifelong fan of the human race I preferred the IA route and dreamed of a day when we would have William Gibsonesque brain machine interfaces (e.g., ala Count Zero) that would augment our brains, make us smarter and let us gobble up all the knowledge we wanted at superhuman speed.

Well, it turns out you can use speech synthesis technology (AKA TTS or Text-to-Speech) to hack the equivalent of a USB port for your brain, right now. No neurosurgery required!

Hacking your brain in 3 unintuitive steps

StdTrap: a magical Pythonic mechanism for intercepting console output

As a programmer I believe less is more. Good code is small, simple and elegant and many times favorable to larger, noisier code that does the same. It's not just about aesthetics either. Making code small and beautiful makes it easier to read, and easier to understand. Which is guaranteed to make it work better. Trust me on this.

A Universe from nothing? Lawrence Krauss

I highly recommend watching the following lecture when you have about an hour of spare time:

How is this related to TurnKey? Good question. Well, the origins of the Universe relate to everything in the Universe right? TurnKey is in the universe, hence the relation. QED.

No Juju for you! Ubuntu's Not Invented Here syndrome

Today Brian emailed me to share his enthusiasm for the Ubuntu Juju project, developed by Canonical, the company that makes Ubuntu.

Brian is a good friend that has been advising us on all matters TurnKey practically since the project began. His advice and feedback is always well informed and insightful so even when I already have my own opinions on the matter, I still take the time to look into his suggestions carefully. Thanks Brian!

Audio video codecs: a video editor's tutorial introduction to codecs

What's a codec?

Raw uncompressed digital video contain a huge amount of information: 3 bytes per pixel translates into roughly 240Mbit/s for standard definition video, 504Mbit for standard HD video (720p), and 1136Mbit/s for full HD video (1080p).

Even at just standard definition (DVD) you'd need over 200GB to store a two hour uncompressed movie which isn't practical for most applications.

Video editing with avidemux and audacity

Not too long ago I explored free software video editing tools for a video demo production I was working on. I was finding it impossible to shoot the whole video in one take without major goofs in a reasonable amount of time while also narrating what I was doing. As usual, I was having trouble because I was trying to do too many things at once, without willing to compromise on quality. When I realized this I decided to be practical and break down my production into bite sized chunks.

tmux is a superior alternative to screen

Today was the first day I stopped using screen and started using tmux, which is a superior alternative which supports a more complex range of splits and has a nicer interface. It's a bit different from screen in that it has this concept of windows and panes. A tmux pane is a window (e.g., shell session) in screen terminology. A tmux window is a layout of panes (e.g., two windows side by side). A tmux window could have only one pane, or it could have an arbitrarily complex configuration of panes.