Isaac Paul izackp

How to setup a practically free CDN using Backblaze B2 and Cloudflare

⚠️ Note 2023-01-21
Some things have changed since I originally wrote this in 2016. I have updated a few minor details, and the advice is still broadly the same, but there are some new Cloudflare features you can (and should) take advantage of. In particular, pay attention to Trevor Stevens' comment here from 22 January 2022, and Matt Stenson's useful caching advice. In addition, Backblaze, with whom Cloudflare are a Bandwidth Alliance partner, have published their own guide detailing how to use Cloudflare's Web Workers to cache content from B2 private buckets. That is worth reading,

I am assuming you are here because like me, you installed a bazillion different python interpreters on mac and the whole thing is a spagetti. Today, I finally fixed my python installation. Whatever I install for python2 or python3 using pip JUST.WORKS.. My god! finally.

What the hell?

Here is what I had messed up, which you also probably did:

I had too many different python interpreters
Too many different symlinks which I lost track of
almost no package I installed with pip worked without a headache
any attempt to fix using online resources made it worse.

Installing .NET Core on Linux ARM64

The following intructions can be used to install .NET Core on Linux ARM64.

Pro tip: Check out .NET Core Docker files to determine the exact instructions for installing .NET Core builds, for example .NET Core 3.1 ARM32 SDK Dockerfile.

Installing .NET Core Globally

The following instructions install the latest .NET Core globally. It isn't required to do that, but it provides the best experience.

Compile Time Constant Expressions for Swift

Proposal: SE-NNNN
Authors: Marc Rasi, Chris Lattner
Review Manager: TBD
Status: Awaiting implementation

Swift-evolution thread: https://forums.swift.org/t/pitch-compile-time-constant-expressions-for-swift/12879

Introduction

Scenario:

multiple USB devices plugged via hub to a host (Linux OS based),
multiple services/programs interacting with TTY running on top (e.g. GPSd)

Problem:

At boot TTY are randomly assigned to devices causing depending services/programs instabilities. They could indeed fail to start because of different TTY configurations.

Solution:

Server image

I use Ubuntu 16.04/Ubuntu Xenial.

Setup server

Add a new user who isn't root, but who can sudo:

Update all the things: apt-get update && apt-get dist-upgrade && apt-get autoremove
Reboot, just in case: shutdown -r now

How to automatically start ssh server on boot on Windows Subsystem for Linux

Microsoft partnered with Canonical to create Bash on Ubuntu on Windows, running through a technology called the Windows Subsystem for Linux. Below are instructions on how to set up the ssh server to run automatically at boot.

Edit the /etc/ssh/sshd_config file by running the command sudo vi /etc/ssh/sshd_config and do the following
1. Change Port to 2222 (or any other port above 1000)
2. Change PasswordAuthentication to yes. This can be changed back to no if ssh keys are setup.
Restart the ssh server:
- sudo service ssh --full-restart
With this setup, the ssh server must be turned on every time you run Bash on Ubuntu on Windows, as by default it is off. Use this command to turn it on:

How to Generate & Use Private Keys using OpenSSL's Command Line Tool

These commands generate and use private keys in unencrypted binary (not Base64 “PEM”) PKCS#8 format. The PKCS#8 format is used here because it is the most interoperable format when dealing with software that isn't based on OpenSSL.

OpenSSL has a variety of commands that can be used to operate on private key files, some of which are specific to RSA (e.g. openssl rsa and openssl genrsa) or which have other limitations. Here we always use

	Install WireGuard via whatever package manager you use. For me, I use apt.

	$ sudo add-apt-repository ppa:wireguard/wireguard
	$ sudo apt-get update
	$ sudo apt-get install wireguard

	MacOS
	$ brew install wireguard-tools

	Generate key your key pairs. The key pairs are just that, key pairs. They can be

	OVERVIEW: Swift compiler

	USAGE: swiftc [options] <inputs>

	MODES:
	-dump-ast Parse and type-check input file(s) and dump AST(s)
	-dump-parse Parse input file(s) and dump AST(s)
	-dump-scope-maps <expanded-or-list-of-line:column>
	Parse and type-check input file(s) and dump the scope map(s)
	-dump-type-refinement-contexts