Tag archive for: system administration

How to deploy Python 3 Flask application on Raspberry Pi 3 with Raspbian Stretch Lite, Nginx, Supervisor, Virtualenv and Gunicorn

Raspberry Pi 3 Model B boards make good gifts for programmers and if someone had gifted you with one, you may want to use it as a control center for interacting with various IoT sensors and devices at home.

In such a situation, you may want to build a Python 3 Flask application to present the web interface for accessing the control center.

After you had built that Python 3 Flask application, the next step will be to deploy it on your Raspberry Pi 3 for serving HTTP requests.

This post discusses how you can deploy a Python 3 Flask application on Raspberry Pi 3 with Raspbian Stretch Lite, Nginx, Virtualenv and Gunicorn.

Configuring Nginx for PHP web applications

Nginx and PHP FastCGI Process Manager (FPM) are often used side by side for PHP applications. In such a setting, Nginx will be the first point of contact for incoming HTTP requests, acting as a reverse proxy server for the PHP FastCGI Process Manager.

The PHP FastCGI Process Manager then interprets the HTTP requests that it receives from Nginx and runs the PHP scripts for generating the corresponding HTTP responses for Nginx to return back to the HTTP client.

This post discusses a set of configurations that you can use for configuring Nginx for your PHP web applications.

Configuring Nginx to serve files for a static website

In the world of HTTP, static files are content hosted on a web server that does not change. Some examples of static files include images, CSS files, JavaScript files and HTML files.

Although it is not too hard to implement a dynamic website through a content management framework like WordPress on your own server, there are cases where it makes more sense to just host a couple of static files to realise your website.

Nginx is an excellent web server for serving static websites. If you already have Nginx running on a Raspberry Pi 3 or any other kinds of server, you may want to configure it to serve files for your static website.

How to migrate your MySQL / MariaDB database with mysqldump, tar and scp

If you had been building the content for your new WordPress site on a Raspberry Pi 3, there will come a time when you need to migrate the underlying MySQL database to another machine, for eg. a DigitalOcean droplet, for production usage.

MySQL provides us with the mongodump client utility to produce a set of SQL statements that can be executed to reproduce the original database object definitions and table data.

A simple MySQL database migration can be performed with the following steps:

1. Use mysqldump to get the set of SQL statements that can be executed to reproduce the original database object definitions and table data.
2. If the mysqldump output is too big, use the tar command to compress it.
3. Use the scp command to send the mysqldump output from the source server to the destination server.
4. If you had used the tar command to compress the mysqldump output, use the tar command at the destination server to decompress it.
5. Execute the set of SQL commands in the mysqldump output at the destination server.

This post documents how you can migrate your MySQL / MariaDB database with utilities provided by MySQL and most Linux servers.

Building a reverse proxy server with Nginx, Certbot, Raspbian Stretch Lite and Raspberry Pi 3

The Nginx reverse proxy server runs well on Raspberry Pi 3 and you can use it behind a router to route HTTP traffic to upstream web applications.

A Raspberry Pi 3 reverse proxy server is a very useful appliance to help us host multiple websites from home.

Some examples of web applications that you may want to host at home includes:

• WordPress site on Raspberry Pi 3
• Raspberry Pi Zero W CCTV for security surveillance
• Fast Git Server based on Go Git Service and Raspberry Pi Zero W
• Codiad Web IDE on Raspberry Pi 3
• ProjectSend for sharing files with my friends
• Python 3 Flask MVP with Supervisor on Ubuntu Server 16.04
• Jenkins running on Raspberry Pi 3 and Raspbian Stretch Lite

This post discusses how you can build a reverse proxy server with nginx, Certbot, Raspbian Stretch Lite and Raspberry Pi 3 to proxy HTTP traffic directed at applications on your home network.

Understanding the difference between the root and alias directives in Nginx

Nginx is a web server that is good for serving as a reverse proxy server, load balancer or HTTP cache.

One of the most important task in configuring Nginx to proxy HTTP / HTTPS traffic is telling Nginx where to look for files that it needs for serving HTTP / HTTPS requests.

This posts discusses the root and alias directives that we can use in Nginx configuration files for mapping a url from a HTTP request to a file on the server file system.

How to setup Raspbian Stretch Lite with remote configuration over WiFi on first boot

Two of the good features of Raspbian Stretch Lite is that it allows us to enable the SSH server and connect to our WiFi network before it boots up for the first time.

Combining these two features is useful for projects based on Raspberry Pi Zero W as we can configure Raspbian Stretch Lite via SSH without connecting extra peripherals to it.

This post documents how you can enable remote configuration of your Raspbian Stretch Lite over WiFi on first boot.

Setting up WordPress on Raspberry Pi Zero W with Raspbian Stretch Lite, Nginx, MariaDB and PHP as the LEMP stack

A Raspberry Pi Zero W is a small and capable computer that included a Wi-Fi chip for projects that requires an Internet connection.

Apart from running client programs on the Raspberry Pi Zero W, it is equally capable of being a web server. Since I had a spare Raspberry Pi Zero W lying around the house and there are good reasons to blog as a programmer, I decided to use it as a WordPress server to collect content for a new blog project.

This post documents how I setup WordPress on a Raspberry Pi Zero W with Raspbian Stretch Lite, nginx, MariaDB and PHP as the LEMP stack.

How to setup Raspbian Stretch Lite on Raspberry Pi Zero W to run Python 3 applications

With Wi-Fi included, the Raspberry Pi Zero W is very useful for implementing embedded projects that require Internet connection.

Apart from using the Raspberry Pi Zero W for CCTV surveillance, we can run customized Python 3 applications on a Raspberry Pi Zero W for various use cases.

Pairing the official operating system for Raspberry Pi with Python 3, we will be able to get a versatile computer to do our bidding.

Anticipating the need to setup a version of Raspbian Lite on Raspberry Pi Zero W for future Python 3 projects, I created this post to document the steps of how to do so with Raspbian Stretch Lite.