Category: Tech

Using an Arduino UNO and 8 strips of Neopixel ws2812 strips (60 LED/m) I was able to recreate the awesome LED sign created by Josh here: https://youtu.be/k-SYMPO8-f8

Needed some text to test it and picked the cf push haiku by Onsi Fakhouri:

“cf push haiku here is my source code run it on the cloud for me i do not care how”

 

By default, if the new installer is utilized when deploying Ubuntu server 18.04, the /etc/apt/sources.list will contain only two entries. This doesn’t cover much, so to expand it to be a bit more useful we replace it with:

deb http://jp.archive.ubuntu.com/ubuntu/ bionic main restricted
deb http://jp.archive.ubuntu.com/ubuntu/ bionic-updates main restricted
deb http://jp.archive.ubuntu.com/ubuntu/ bionic universe
deb http://jp.archive.ubuntu.com/ubuntu/ bionic-updates universe
deb http://jp.archive.ubuntu.com/ubuntu/ bionic multiverse
deb http://jp.archive.ubuntu.com/ubuntu/ bionic-updates multiverse
deb http://jp.archive.ubuntu.com/ubuntu/ bionic-backports main restricted universe multiverse
deb http://security.ubuntu.com/ubuntu bionic-security main restricted
deb http://security.ubuntu.com/ubuntu bionic-security universe
deb http://security.ubuntu.com/ubuntu bionic-security multiverse

Note that this is for Japan (“jp”). Change this to “us” or similar to match your region if not in Japan.

If your system is using netplan for network configuration, change settings in “/etc/netplan/50-cloud-init.yaml”:

DHCP:

jonas@kube-c1-n3:~$ cat /etc/netplan/50-cloud-init.yaml
network:
    ethernets:
        enp0s3:
            addresses: []
            dhcp4: true
    version: 2
jonas@kube-c1-n3:~$ sudo netplan apply

Static IP:

jonas@kube-c1-n3:~$ cat /etc/netplan/50-cloud-init.yaml
network:
    ethernets:
        enp0s3:
            addresses: [192.168.10.103/24]
            gateway4: 192.168.10.1
            dhcp4: no
    version: 2
jonas@kube-c1-n3:~$ sudo netplan apply

Note that “gateway4” should only be set for the default route interface.

If one disconnects an external monitor / projector the Atom editor window has a tendency to show up outside of the screen boundaries – just as if the external monitor was still attached. It took a while to figure out how to get it back again:

1. Select the Atom window (using Alt-Tab or mouse)
2. Open the context menu with Alt-Space
3. Select move using “m”
4. Press any of the arrow keys
5. The Atom window will now be possible to drag back to the main monitor using the mouse

This was mentioned in a GitHub thread here: https://github.com/atom/atom/issues/6939

 

Add the following line at the end of /etc/sudoers (just after “#includedir /etc/sudoers.d”):

username ALL=(ALL) NOPASSWD: ALL

In my case:

#includedir /etc/sudoers.d
jonas ALL=(ALL) NOPASSWD: ALL