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Every computer needs an operating system – and the Raspberry Pi is no different. Primarily, the Raspberry Pi boots from an SD card. But how do you write an operating system to that SD card? Well, if you’re just starting out – then this is the video for you!
Adding unnecessary components to the Kernel is generally a bad idea, as it increases its threat surface. In this episode, Jay and Joao discuss a recent story that’s a perfect example of why it’s important to keep this under control. A vulnerability was recently discovered in the Linux kernel that scored the highest possible rating, and it all started when ksmbd was added.
If you have one or more servers that need to always be available and ready for action, how do you keep track of uptime? How can you receive alerts to notify you when there’s an issue? In this episode, Tom and Jay discuss some of the tools they use to monitor servers and important metrics.
With the Linux Crash Course series on LearnLinuxTV, you’ll learn everything you need to know in order to master the art of Linux. In each video, a single topic is covered in-depth. This time around, we take a look at the ls command – a command that many of you have probably already used, but there’s always more to learn!
Thanks to Linode for sponsoring today’s video! Definitely check them out – you can have your very own Linux server set up in mere minutes!
When it comes to patching, were you aware that there’s more than one type of patch? In this episode of Enterprise Linux Security, Jay and Joao discuss the various types of patching that’s performed today.
System76 recently expanded their line of Linux laptops with a new Oryx Pro model – complete with DDR5 and a 4K OLED display! In this video, Jay will give you his thoughts on this latest model. This review will go over specs, build quality, performance, and more!
Recently, I decided to check out ThinLinc – a remote desktop solution for Linux. With client apps for Linux, macOS and Windows – it’s easy to set up and configure. In this tutorial, I’ll give you an overview of the solution and walk you through the process of setting it up. Please note that this is a tutorial/setup guide, and not a review.
When it comes to computing, it’s often said that the key to efficiency is to not repeat yourself. That’s true. Except for the the watch command – it’s intended use-case is to repeat a command over and over. Believe it or not, it can really come in handy. Learn all about the watch command by watching this watch tutorial.
Thank you to Linode for sponsoring today’s video! Check out their awesome cloud platform and set up your very own Linux Server!
Open-Source is great – with code being open, everyone has access to it. That means that the code can be audited – and that makes it more secure, right? Well, possibly. In the recent talk “The Code is Open, But Who’s Looking at it?” Joao discusses the concept in detail. This talk was recorded at OSAD 2022. New episodes of Enterprise Linux Security will resume after the holidays. But for now, enjoy the talk!
When building a new virtual or physical server, doing everything manually is a waste of time. With an image or template, you can have some of your recurring tasks already set up on the image – and then every instance you create from that template will have all of those tweaks already made. But how far should you go with this default setup? What are some of the caveats that you might run into? In this episode, Jay and Tom discuss creating server images/templates and the related shenanigans you may run into while doing so.
Here’s another blog post today, that I’m creating for the same reason as the previous one. It took me a bit longer than I’d like to admit to figure this out, and if anyone else out there is wondering why their automated Kubernetes builds on Ubuntu 22.04 started failing on them suddenly for no apparent reason. Specifically, your Kubernetes cluster builds started failing on December 9th. (You literally can’t make this stuff up). So, after troubleshooting for countless hours I finally figured it out. I mentioned it to Jeff Geerling (yes THAT Jeff Geerling) and he mentioned I should write a blog post, in case it may help someone else. I figured that his suggestion was logical 🖖, so here it is.
What’s the problem I’m referring to? If you’re attempting to initialize a Kubernetes cluster on Ubuntu 22.04 and you see error messages that include output such as this:
CRI v1 runtime API is not implemented for endpointOr maybe even this:
unknown service runtime.v1.RuntimeServiceContinue reading and I’ll let you know what the issue is, and how to fix it. I’ll also sneak in a quantum science reference and it’s going to be a good time.
(more…)Normally, I like to make videos for Linux and Container-related things – it’s my favorite way to teach and inform. But some things don’t translate as well to videos, and this is one of them. Recently, I ran into an issue that I’ve been trying to solve for some time, where initializing a Kubernetes cluster on Ubuntu 22.04 seems to fail, specifically on the Raspberry Pi. Although I did ultimately find something while searching the web that led to my resolving this, search results were generally unhelpful, and neither was Stack Overflow. So what I wanted to do, was to create this article just so I could make sure that anyone else Googling for answers does find something.
Here’s the issue I ran into. For some reason, initializing Kubernetes clusters on Ubuntu 22.04 fails on the Raspberry Pi. More specifically, Flannel doesn’t seem to launch, with it stuck on “CrashLoopBackoff” most of the time. And not only that, the coredns pods will tend to stay stuck on “ContainerCreating” for eternity. Another symptom is that you’ll find errors in /var/log/syslog complaining about /run/flannel/subnet.env not being found. Oh, and another symptom. RPC errors will be mentioned in the syslog as well, and also complains about not being unable to create the sandbox.
Blogs and howto’s mention many “fixes” for this issue, but for me I didn’t have any luck there. Some of them will have you create the /run/flannel/subnet.env file manually – but you shouldn’t have to do that, it’s not your job. (That file should be created automatically). I’ve seen at least one blog post mention the order matters regarding when you apply Flannel (nonsense) and not to be outdone, the classic “remove the directory and reboot” trick that also never seemed to work for me.
So, what’s the fix?
Are you ready?
Here you go…
sudo apt install linux-modules-extra-raspiYeah, that’s literally it. I’m not kidding. See for yourself. You’re all set. Profit. Enjoy. I know, right?!
Thanks to this completely unrelated bug report that gave me the idea to install this package and ultimately led to my writing this article. It’s my sincere hope that this blog post finds its way into the Google searches of whoever out there needs this.