Installing VirtualBox is getting increasingly painful on Ubuntu due to the problems with UEFI Secure Boot and the VirtualBox kernel modules. Another reason for an alternative is that running VirtualBox VM’s completely in the background is not as straightforward as it could be.

From the available alternatives I looked into (VMWare, Xen & KVM) it was KVM that fitted my needs (casual VM usage with mostly headless VM’s for testing purposes). Main reasons:

Having just wasted a few hours on getting this Java software running on Linux I am documenting this for future reference and hopefully saving other LoRa / TTN folks some time.

Prerequisites

Install a Java JDK + JavaFX. This should work with the default OpenJDK 8 or 9 which comes as part of the Ubuntu repositories. I ended up installing Oracle JDK 8 as well as I thought the error might be related to OpenJDK.

Install XScreenSaver and remove Gnome default

sudo apt remove gnome-screensaver
sudo apt install xscreensaver xscreensaver-gl xscreensaver-gl-extra

Run the Screensaver UI and configure

In the “Advanced” section enter your Flickr RSS URL in “Choose Random Image”

https://api.flickr.com/services/feeds/photos_faves.gne?id=YOURFLICKRUSERID #replace with your Flickr User ID

Create a systemd user service to autostart

mkdir -p ~/.config/systemd/user/
vim ~/.config/systemd/user/xscreensaver.service

[Unit]
Description=XScreenSaver
[Service]
ExecStart=/usr/bin/xscreensaver -nosplash
[Install]
WantedBy=default.target

Start and enable systemd user service

systemctl --user enable xscreensaver
systemctl --user start xscreensaver

To copy the settings (including RSS URL) onto other PC’s or re-install it might be a good idea to backup or copy the contents of ~/.xscreensaver

I recently purchased a GrovePi Zero and expected this to be a reasonable straight forward way to connect Grove sensors to your Raspberry Pi, read sensor values via Python and pushing them upstream via MQTT. However the software side of things turns out anything but straight forward. Most of the suggestions on the Dexter Industries forum suggest to download some custom OS image – WTF? Hopefully this will save some people time to chase down the same rabbit holes…..

If you are using the GUI (Raspian full download) and want to connect your RPi Zero to a keyboard and monitor there are probably easier ways to do this. These notes are for people that want to use a headless (no monitor and GUI) setup ready to connect to your RPi after first boot via SSH from another terminal.

“Raspberry Pi Zero W” (CC BY-SA 2.0) by lespounder

EDIT [2018-06-05]: I have updated the code with the Firmware 1.18.+ releases. The code is available at our Growing Data Foundation Github.

These notes are to assist Australian IoT enthusiasts to get started in connecting a LoPy to The Things Network as it is unfortunately (not yet) straight forward to make them work with the current AU-915 TTN Channel plans. As the initiator of the local Adelaide Community of The Things Network I have been experimenting with a number of devices to connect sensors to #TTNADL. One of my personal favourites is the Pycom LoPy as a nice middle-ground between capabilities and technical complexity.

Since Synology (despite requests) still has not added DNS Made Easy as a listed provider (despite listing some really obscure services – go figure!) here is the steps to add a custom provider.

DNS Made Easy Setup

Create a new A-Record

1. Set the name
2. Set the IP (initial – any valid IP)
3. Tick the “Dynamic DNS” tickbox
4. Enter your chosen Dynamic DNS Password
5. Save the new record

When saving the record you will see a “Dynamic DNS ID” – note down this number. This will become the hostname on the Synology setup.

Upgrade or install SANE backends

Since the version of SANE in the Ubuntu 16.04LTS repos is not working for this scanner you either need to install from sources (see this blog) or from this PPA.

sudo add-apt-repository ppa:rolfbensch/sane-git

sudo apt update sudo apt install sane-backends tesseract-ocr gscan2pdf`

Security

Add yourself to the ‘scanner’ group to be able to use the scanner.

sudo usermod -a -G scanner USERNAME

Checking SANE

Check for the libsane version (needs to be at least libsane.so.1.0.26 not libsane.so.1.0.25 which is in the Ubuntu repos)

Since there is now a supported Raspbian version without GUI and other unneeded add-ons available as Raspbian Lite the need to use other installers (with sometimes some downsides) is now not a necessity anymore. Below is a list of steps I like to perform before using them for any purpose as my Standard Operating Environment.

Download Raspbian Lite

Download link: https://www.raspberrypi.org/downloads/raspbian/

Write to SD Card

dd bs=4M if=2016-05-27-raspbian-jessie-lite.img of=/dev/sdb

Boot RPi

Default login details are
UID: pi
PWD: rasbperry

I haven’t been using Opera for quite a while as I didn’t really have a need for a third browser lately (Firefox & Chrome being the main ones). However I came across this article today mentioning that Opera has integrated ad-blocking as a core feature rather than a plugin to manage.

If there were no bloated ads, some top websites would load up to 90% faster.

Today, we wanted to share with you a native ad-blocking technology in our Developer channel for Opera for computers. “Native” means unmatched speed vs extensions, since the blocking happens at the web engine level.

Whilst there is a .DEB installer to download from the GoHugo sites I get all matter of warnings that the package is of bad quality and I am not comfortable to run these kinds of installers.

I rather install from sources in this case which is very straight forward since the main dependencies (largely GO) are in the Ubuntu main repositories.

Install dependencies

sudo apt-get install golang git mercurial python-pygments

As a long-term Ubuntu user I am extremely interested in what Canonical and the Ubuntu community are doing on the mobile front. Their convergence strategy (I am testing Snappy Core on IoT devices as well) seems very well thought through and once the the Meizu MX4 phone was released I got myself an invite and ordered a unit. It took a while to ship and then also had to make it’s way down under as Meizu only ship to Europe (and Asia I believe).