Major Hayden major

Linux Mail Server

In this guide, I will show you how to make a Linux Mail Server in fast and easy way. This guide was taken from tiq's tech-blog for recent version, Linux distro I using is Ubuntu 20.04 LTS

Certificate

Make sure you have Certificate and Key file ready to use.

You can use existing Web Server SSL certificate, since we going to use same domain, example.com.

If you plan to use mx.example.com or mail.example.com you need create another one for these.

Programming Media Keys on the Ducky One 2

To use media keys on the Ducky One 2, you must record a macro to bind the media function to a hotkey combination, i.e. Fn plus some key.

Example

Important: In the instructions below, "Press X+Y+Z" means press and hold key X, press and hold key Y, press and hold key Z in that order, and then release all three.

As an example, to bind Fn+PgUp to the play/pause media function:

Dell OS Recovery Tool Under Linux Mini-HOWTO

Since I was unable to find a specific answer to how can one create a Dell recovery disk from within Linux, I decided to write the steps here.

If you write the CD image directly to the USB drive (or create a new partition and write it there), the laptop will not boot. You need your USB media to be in FAT32 format with the contents of the recovery ISO.

Download the recovery ISO from the support section of Dell website.
Insert a USB Drive with enough capacity to hold the contents of the ISO image.
Format the drive and create a filesystem where $USB_DEVICE is your USB drive (check with fdisk -l, it may be

	#!/bin/bash
	set -euo pipefail
	IFS=$'\n\t'

	# Download all ticked blocklists from The Firebog's "The Big Blocklist
	# Collection" [0] and block access to them with Unbound by redirecting traffic
	# to 0.0.0.0.
	#
	# [0]: https://firebog.net
	(

	# Those rules protect HTTP/HTTPS services for both IPv4 and IPv6 sources as such:
	# 1. Prevent a /32 IPv4 or /64 IPv6 to open more than 10 HTTPS?/TCP connections per second (the limit is high, but this still shield against some attacks) — DROP TCP packets in this case, to avoid generating egress traffic sending a RST
	# 2. Limit ingress bandwidth to HTTPS? services to 32KB/sec (adjust to your needs, in my case it is used to shield a WebSocket backend against incoming WebSocket message floods)
	# 3. Limit the number of simultaneous ongoing connections to HTTPS? to 40 (also, high limit, adjust to your needs)

	# The protections those rules offer:
	# 1. Prevent crypto-DOS (ie. a client that proceed too many key exchanges and thus exhaust server CPU)
	# 2. Prevent WebSocket floodings (eg. I use this for Socket.IO, which has no efficient way to rate-limit received messages before they get parsed)
	# 3. Prevent ephemeral TCP port exhaustion due to a client holding too many TCP connections
	# 4. Prevent IPv6 rotation attac

	# This is a step by step tutorial on how to run uwsgi in emperor mode,
	# behind nginx on Fedora 20. I'll add to the tutorial as time goes on.
	# SeLinux will likely be a pain (even in permissive mode), so please see my comment on how to fix it.

	sudo yum upgrade

	sudo yum install nano yum-utils gcc uwsgi-plugin-python3 nginx

	yum-builddep python3-psycopg2

	'''
	Copyright (c) 2011, Richard Nienaber
	All rights reserved.

	Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

	Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
	Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
	The name of 'Richard Nienaber' may not be used to endorse or promote products derived from this software without specific prior written permission.