Ruby & Serial Ports - A Debugging Adventure

So as part of my ongoing "playing around" with model railway control I treated myself to a 16 zone RailCom receiver from DCC₄PC, in part because their documentation is so clear about how to talk to their devices using software you've written yourself. Enter a shelf kit with 7 pieces of setrack individually wired, a DCC command station (DCC++EX) and some DCC₄PC parts.

Robots and Brownies

I'm currently doing the new Digital Maker badge with my Cubs and last night I found myself at my friend's Brownie pack doing some of the activities I did (or will be doing) with my Cubs. With only an hour I had to reduce what I was planning but most importantly the girls had fun (rule 0 of Guiding)!

Using SSH agent for sudo authentication on Ubuntu

Thanks to a post at www.drhevans.com/blog/posts/195-using-ssh-agent-for-sudo-authentication/ I got a starting point, however a few things didn't quite work out (I had to install checkinstall as a prerequisite and edit the client machine user's ssh config) so here's the adjusted instructions (updated Feb 2015). You can chckout the project on GitHub - github.com/cpick/pam-ssh-agent-auth

Logwatch a Custom Log File

So I own a VPS (if you can ever really own a VPS) which does a number of things for me. It's backed up by the hosting company, something which requires root access. Now I always worry when giving someone root access, no matter how much I trust them, so the back ups are performed through a simple script which only allows certain commands to be ran, as well as logging all attempts.

New Take on Passwords

The otherday I watched episode 303 of Security Now and Steve has a very interesting take on passwords. Essentially assuming we don't have a dictonary word then it's all about using as many different types of characters as possible. Yes length still matters but entropy (randomness) doesn't. By not having an easily guessed password you're forcing an attacker to do a brute force attack and by having as many different types of characters as possible you're increasing the number of passwords they have to guess. Steve's put a page up on his website to demonstrate this point - www.grc.com/haystack.htm.

Umask Values

Another post containg stuff I usually have to look for.

Rails 3 on Apache on Ubuntu 10.04

So I was investigating how to run a rails app on my VPS. I needed to use several sources to get little bit's working, so here's the combined instructions. Note that I assume you're starting with a working apache installation.

Fix Grub (Again)

So thanks to Windows going screwy again I had to fix grub on my machine. So I can find these instructions again here they are:

Now I Git it

I've been playing around with git for a short while now and now I think I've finally got it, or rather the point of it. Ignore those places that discuss it as you commit to your local repository and then commit that the the main repository etc. No it's about letting everyone have a complete copy - in fact you don't even need a central repository to get the benefit of version control - it sits there in a folder on your own PC.