Car Computer Raspberry Pi 3 Upgrade

Raspberry Pi 3 upgrade for the Car Computer Recently I wrote about my car computer project based on the Raspberry Pi 2. The performance while acceptable in most situations, would drop and get noticeably sluggish during resource intensive activities such as processing large play queues or music directories. The free space around the [...]

By |March 7th, 2016|Hardware, Linux|9 Comments

Building a Raspberry Pi Car Computer

6 months ago I bought an 80 series Toyota Land Cruiser and the time since has been doing the car up in preparation for a trip around Australia. Since its release the 80 Series Land Cruiser has earned itself a reputation as a dependable and an almost unbeatable machine off road. But given the advances [...]

By |February 7th, 2016|Linux, web development|19 Comments

Changing the Linux Mint Login Background Images

Newer versions of Linux Mint use MintX as the default login screen greeter. By default it comes with a predefined collection of images. These display in the background and change periodically in a slide show type format. The default images are great but I wanted to add a personal touch to my system and change [...]

By |February 1st, 2016|Linux|4 Comments

Raspberry Pi 2 Bitcoin Node

Not long ago I set up a Bitcoin node on a Debian Wheezy VPS to teach myself about Bitcoin and the blockchain in general. It was a great learning experience but the memory requirements of the Bitcoin software kept causing my VPS instance to run out of memory. So the kernel would constantly be killing off the bitcoind process. A growing blockchain also meant the node was getting close to the limit of its available disk space as well. Increasing the amount of disk space available to the VPS instance with the plans offered by the hosting provider was going to be prohibitive for the purpose. So I was forced to assess other solutions. Luckily I had a spare Raspberry Pi 2 that I had yet to do anything with at home. So I made the decision to try and install a Bitcoin node on that instead to save some money. The main expense with using the Raspberry Pi was going to be finding enough storage for the block chain. I didn’t have an SD card that was big enough at home to accommodate the operating system image and the block chain. So I opted to buy a cheap external USB flash drive to keep it separate from the root filesystem. After formatting with ext4 the flash drive has 57Gb of available space, at the time of writing the blockchain takes up 40Gb of space so that leaves a further 17Gb for future growth. […]

By |May 26th, 2015|Hardware, Linux, Open Source|0 Comments

Running a Bitcoin Node on Debian Wheezy

Over the last few years I have keenly followed the rise of Bitcoin from its early days trading at around $8USD. I watched with interest when it made its sharp rise to $1200USD and then felt dismay with more recent decline back to around the $200USD mark. As a whole I think Bitcoin and the Blockchain are both game changing technologies that are yet to see their full potential. So over the last few months rather than just watching the Bitcoin exchange rate bounce around the place. I sought to get a deeper understanding of how the underlying technology works and how it can be extended further. As part of this learning process I decided to set up a Bitcoin node both to act as learning resource for myself and to help contribute something back to the larger Bitcoin network. In this article I am going to run through the process of turning a VPS running Debian Wheezy into a fully fledged Bitcoin node. […]

By |January 22nd, 2015|Linux|0 Comments

Creating a Simple Iptables Blacklist

Anyone that had ownership of  a server for any length of time quickly learns that the Internet is full of spammers, bots and other characters you would prefer didn’t exist. A firewall is key to keeping these guys at bay and Linux comes with a Kernel level firewall called iptables that can be employed for this purpose. The only downside of iptables is that people who don’t deal with it on a regular basis tend to find its syntax a little bit daunting. In this post I am going to run you through the process of setting up a basic firewall IP blacklist. Using a bash script to read list of blacklisted IP addresses and feeding these to iptables so they can no longer access your server. Creating the Script First up create decide where you would like the script to live. for this example I am just going to put it in /root/scripts. i.e mkdir /root/scripts nano firewall.sh […]

By |June 16th, 2014|Linux, Security, Uncategorized|0 Comments

Creating a Tor Relay on Debian

The TOR project has proven itself an indispensable tool in the fight to protect the anonymity of people on-line. The project needs servers to route traffic through for the project to achieve its goals though. So contributors are needed to donate relays nodes ensuring a free Internet for all. In this post I am going to run you though the process of installing TOR and configuring a relay service for use by the network on a Debian system. Installing & Configuring Tor First up login to your machine via a terminal, update the package library and install the Tor server: apt-get update apt-get install tor Then change into the Tor config directory cd /etc/tor […]

By |June 12th, 2014|Linux, Security|0 Comments

Linux CLI: File Text Search & Replace

Occasionally you need to change the contents of some files easily to save a lot of manual work. In my case it was a server migration, the old IP address of a server was referred to from numerous DNS records. This meant the contents of a couple of hundred Bind zone files would also have to change so that they would reflect the new server address. This is task that would take way too long to do manually, luckily grep and sed can automate the process. In this post I will show you how to recursively search for and change a string in all files that exist below a directory. The format for doing a recursive search / replace looks like: grep -rl ‘search_term’ ./ | xargs sed -i ‘s/search_term/replacement_text/g’ […]

By |December 19th, 2013|Linux|0 Comments

Encypting Diectories With eCryptfs

eCryptfs is an encrypted file system that works at the file system level. In this post I am going to cover the basic usage of eCryptfs and some of the situations you may want to think about using a encrypted file system. What is an encrypted file system? File system encryption protects information by converting [...]

By |December 14th, 2013|Linux|0 Comments

Debugging Web Applications With Fiddler On Linux

Fiddler is by far one of the most popular web debugging proxies available. It allows you to capture, examine, save, edit and replay all HTTP / HTTPS  requests made by a web based application. For many years it was available only on Windows systems. But recently the creator of Fiddler, Eric Lawrence has released a version of Fiddler that runs using the mono runtime allowing it to run successfully on MacOS and Linux platforms. In this post I am going to run through the basic setup and usage of fiddler under Linux (I am using Linux Mint 15 the process should not vary too for other Debian based variants though). First up visit the fiddler site and download the alpha mono version of the application. After downloading unzip the package and copy the mono version of fiddler to the directory where you would like it to live on your system (I am simply using a folder named Software in my home directory). […]

By |August 28th, 2013|Linux, web development|2 Comments