Red Hat Enterprise Linux 9 (RHEL 9) and Docker don’t get along very well. Running a container that requires older iptables (and not nftables) can be a problem.
Tag: Linux
How to add an inline comment using Ansible.
The year is 2021, and I need to write a Windows Batch Script to get Helm Post-Renderer working on Windows so I can deploy my application to Kubernetes.
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.
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.
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..
Managing firewalld can be a tricky. Especially if you have many servers to manage. Ansible can help manage firewalld rules for you!
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 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?
