Understanding Firewalld in multi-zone configurations

http://www.linuxjournal.com/content/understanding-firewalld-multi-zone-configurations

Simplify remote access with custom SSH connections

http://www.tecmint.com/configure-custom-ssh-connection-in-linux/

LibreOffice 5.3 on Ubuntu

http://sourcedigit.com/21909-install-libreoffice-5-3-on-ubuntu-linux/

Protecting your Privacy with Firefox

https://linuxconfig.org/protecting-your-privacy-with-firefox-on-linux

EncryptPad on Ubuntu

http://sourcedigit.com/21879-encrypted-text-editor-linux-secure-text-editor-linux-ubuntu/

Install Arch via Revenge

https://www.ostechnix.com/installing-arch-linux-using-revenge-graphical-installer/

Rewrite URLs (Apache on Xenial)

https://www.digitalocean.com/community/tutorials/how-to-rewrite-urls-with-mod_rewrite-for-apache-on-ubuntu-16-04

Using ssh-agent and ED25519 Keys on GNOME

https://eklitzke.org/using-ssh-agent-and-ed25519-keys-on-gnome

Stretch LAMP server

https://linuxconfig.org/how-to-install-a-lamp-server-on-debian-9-stretch-linux

Min on Ubuntu

http://sourcedigit.com/21906-install-min-on-ubuntu-a-faster-web-browser-for-linux-ubuntu/

Improve VirtualBox guest performance

http://www.techrepublic.com/article/how-to-improve-virtualbox-guest-performance-in-five-steps/

Reverse proxy on Jessie (Apache)

https://www.digitalocean.com/community/tutorials/how-to-use-apache-as-a-reverse-proxy-with-mod_proxy-on-debian-8

OpenSSH key walkthrough

http://kyleisom.net/articles/ssh_keys.html

Ubuntu package management (5)

http://www.ubuntubuzz.com/2017/01/ubuntu-package-management-part-5-basic-synaptic.html

Qubes series (4)

http://www.linuxjournal.com/content/secure-desktops-qubes-extra-protection

NTP series (3)

https://www.linux.com/learn/2017/2/arrive-time-ntp-part-3-secure-setup