The bash prompt can be adjusted to ones needs, see this manual page. For example, you can display the current user, directory and time. The Ubuntu default prompt looks like this: PS1=’${debian_chroot:+($debian_chroot)}[\033[01;32m]\u@\h[\033[00m]:[\033[01;34m]\w[\033[00m]\$ ‘ It is also possible to add the
Ubiquiti UniFi Access Points
In our three-story concrete house our old WiFi situation wasn’t optimal to say the least. I used to have an all-in-one router/switch/wifi thing which worked reasonably well on the first floor, but any device on the second or let alone
Docker Cheat Sheet
The Docker cheat sheet provides some examples of commands for building images, running containers, etc. Build an image from the Dockerfile in the current directory and tag the image: docker build -t myimage:1.0 .List all images that are locally stored
Test TCP connection without telnet or nc
Sometimes you need to test if a network connection works without actually using the intended client program. Normally you would use a tool like telnet or nc to do this, e.g. $ telnet www.google.com 80 Trying 172.217.20.68… Connected to www.google.com.
PV Display
PV Output Display is an Android app to view data on the PV Output website. You can view live solar panel data and browse through historical data. The data is presented in five different tabs in both graphical and tabular
Enable HTTPS on Jenkins
Jenkins uses HTTP by default. You can enable HTTPS by performing a couple of steps. You need to acquire an SSL certificate and corresponding key for a domain that is under your control, and tell Jenkins that it needs to
Enable HTTPS on Gitlab
The Gitlab self-hosted application uses HTTP by default. You can enable HTTPS by performing a couple of steps. You need to acquire an SSL certificate and corresponding key for a domain that is under your control, and tell Gitlab that
Monitoring hosts with CollectD, InfluxDB and Grafana
In this article we will install a monitoring solution on CentOS 7 consisting of CollectD, InfluxDB and Grafana. The first step is to install CollectD: yum -y install epel-release yum -y install collectd At the time of writing, this resulted
Linux network auto shutdown from APC UPS
The APC Smart-UPS series of UPS devices allows you to power servers and switches when there is a power failure in the grid. When the UPS is running on batteries, you want your servers to be notified and properly shutdown.
Serialize and deserialize a list of polymorphic objects with GSON
GSON is a great Java library for serializing and deserializing objects to and from JSON strings. When you have a list of polymorphic objects you want to serialize and deserialize, things get a bit more difficult. You have to tell