For example, we assume that the packets received at the Node A’s interface “” will be forwarded from another interface “” to the destination Node B “”.

Forward From Node A ( to Node B (

In the f ...


NOTICE: Certbot-auto can NOT Work on Ubuntu 20.04

Generally we can download certbot-auto and use it by using like the following commands,

wget mv certbot-auto/usr/local/bin/certbot-autosudo chown root/usr/local/bin/certbot-autosudo chmod 0755/usr/local/bin/certbot-auto

Example: Get a certifi ...


TELLO EDU is a programmable drone provided by RYZE and powered by DJI. Although it is a kind of toy drone, but It is a good product to learn drone programming with multiple languages such as Python, and Swift. Let’s take off.

Purchase through DJI and Wait.

You can purchase TELLO and TE ...


This is quick setup guide to connect to Ubuntu 20.04 via Remote Desktop.

Install xrdp with apt commandsudo apt updatesudo apt install -y xrdpsudo systemctl restart xrdpConnect from Windows 10 to Ubuntu 20.04

Open RDP on Windows 10 . Before you connect from Windows to Ubuntu via RDP, I recomm ...

Development,React Native

Expo CLI Tool

Expo is a third-party service. It removes a lot of complexity, and provides lots of convenience & utility features.


In other words, It is a thin extra layer between your app and the vanilla React Native.

For detail, you can find the first step here “

Rea ...