Secure Docker with iptables firewall and Ansible

Out of the box, security with Docker (and Docker Swarm) over the network is bad. Okay, that’s not entirely true. Out of the box when you have no containers started, it’s fine. But after you start a container, and if you publish a port, they are exposed to the outside world by default. And it’s not easy to fix. You need to create a custom Docker firewall with iptables.
 

How to fix Ubuntu 20.04 in 1 step

There’s not a lot wrong with Ubuntu 20.04. So it’s pretty easy to fix the one thing that’s missing! Hint: Install the Cinnamon Desktop.

Docker and the iptables INPUT chain

When testing Docker and iptables I stumbled upon something interesting. It appears Docker uses the iptables INPUT chain in an undocumented way. Well that’s interesting..

Manage firewalld with Ansible

Ansible manage firewalld Managing firewalld can be a tricky. Especially if you have many servers to manage. Ansible can help manage firewalld rules for you!

Find Version Tag for Latest Docker Image

If you’ve ever used Docker, you’ve probably used the latest Docker image tag. This is bad. Do not do this! You will be in a situation where you need to find what version you were actually using. This is how you can find the version of that “latest” image you have running.

Ansible Role to Test Network Connectivity

Ansible is used to do so many things. And if you already use Ansible for your automation tasks then you already have it ready to go. So why not use Ansible to test network connectivity?

5 Reasons Why You Should Upgrade Windows to Linux

Tux

It’s time. Windows users, Upgrade to Linux. Windows 7 is reaching the end. You must upgrade. Do not replace Windows 7 with Windows 10. That is not an upgrade! Upgrade Windows to Linux Mint. It’s so much better!
 
 

User Management with Ansible

Ansible is a great tool to automate all the things. Another task it can help to automate is user management. This guide will be talking specifically about user management on Linux servers like Red Hat Enterprise Linux (RHEL), CentOS, or Ubuntu. Ansible can handle this task!

Upgrade SSH keys and use gpg-agent with Ed25519 keys

SSH keys are convenient and more secure than using a password to authenticate. If you created your SSH key a while ago, it’s probably time to generate new RSA 4096 and Ed25519 keys. SSH keys like DSA and RSA 1024 are very old and now insecure. You should even upgrade ssh keys that are RSA 2048.

Getting Started with Ansible on Ubuntu or CentOS

Setup Ansible - Getting Started with Ansible This is a guide to getting started with Ansible. By the end of this guide, you will be up and running with Ansible.
Included is an Ansible role that will create a user which is used by Ansible to connect to your remote servers. Let’s go! After installing Ansible, you will need to setup Ansible by following these steps.