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Converting an old MacBook into an always-on personal Kubernetes cluster

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Re: Converting an old MacBook into an always-on personal Kubernetes cluster

#91

Post by aliswe »

usui wrote: post #49
johnchristopher wrote: post #47

There are things I don't understand with Kubernetes and the "spin up containers as needed". How do you spin up different databases ? It won't sync, unless your code takes that into account... Say, I have a simple WP site running with a web, a php and a db container... What's the schema to give 2 or 3 more database container and still have visitors see the same content ? (and the databases being consistent) Set up rep…

To tackle this issue in Kubernetes (specifically for a db), I have created persistent volume claims that are mounted across replicas in a db deployment, with the permission of multiple readers but only one writer. If we know that Postgres stores all its data in /var/x, then we can mount /var/x in all replicas as a shared volume. In terms of the point related to taking into account in your application, as long as you…

From what I understand thos is what you need kubernetes database operators for. They configure the database cluster for you.

Re: Converting an old MacBook into an always-on personal Kubernetes cluster

#92

Post by ukd1 »

odensc wrote: post #62
wpietri wrote: post #45

For what it's worth, I built one like this on an old Linux laptop. I then moved my home lighting controller onto it as a test. Some months later my house lights stopped working, and I had to spend a few hours applying snippets semi-randomly from Stack Overflow. It could be the problem was due to expired Kubernetes certificates, or it could be something else. Either way, my conclusion was that Kubernetes is really mea…

FYI, if you're looking to deploy a hobbyist/side-project Kubernetes cluster I'd highly recommend k3s [1] - it's a lightweight certified distribution, and is ridiculously easy to set up. I haven't needed to do any maintenance besides the periodic update. It also works fine for production in my experience, I have a mildly popular website running on a 4GB VPS with it and haven't had any issues related to k3s itself. [1]…

Similar, and probably slightly easier from my experience, plus supports things like clustering and easily managing service, is microk8s[1] from canonical.

[1]: https://microk8s.org

Re: Converting an old MacBook into an always-on personal Kubernetes cluster

#93

Post by teejmya »

fortran77 wrote: post #90

I've had bad luck keeping laptops powered 24/7 for months or years. The battery always swells and fails.

Yes, this is inevitable if you're going to run this plugged in over a significant amount of time. Should remove the battery.

I found no mention of this in the article, which I think is dangerous. Unfortunately I didn't find any way to contact the author on his site (except an unused comment plugin).

Re: Converting an old MacBook into an always-on personal Kubernetes cluster

#94

Post by tuananh »

ukd1 wrote: post #92
odensc wrote: post #62

Earlier quoted context omitted.

FYI, if you're looking to deploy a hobbyist/side-project Kubernetes cluster I'd highly recommend k3s [1] - it's a lightweight certified distribution, and is ridiculously easy to set up. I haven't needed to do any maintenance besides the periodic update. It also works fine for production in my experience, I have a mildly popular website running on a 4GB VPS with it and haven't had any issues related to k3s itself. [1]…

Similar, and probably slightly easier from my experience, plus supports things like clustering and easily managing service, is microk8s[1] from canonical. [1]: https://microk8s.org

it's actually https://microk8s.io

Re: Converting an old MacBook into an always-on personal Kubernetes cluster

#95

Post by xenophonf »

pantulis wrote: post #71
jariel wrote: post #61

Why would one want a 'personal kube cluster'?

For learning purposes, I guess.

Or if you want to self-host. I'm not a huge fan of ceding my digital life to the likes of FAANG, even though I use their services a lot. Conversely, running my own infrastructure (DNS, email, etc.) is kind of a pain, and it'd be nice to apply the same kinds of personal force multipliers to my home setup that I use at work (config management, security benchmarks, automatic provisioning, version control, etc.)

Re: Converting an old MacBook into an always-on personal Kubernetes cluster

#96

Post by spalas »

xwdv wrote: post #67

A better thing to do with an old MacBook is using it for an Arcade cabinet. I wish the person who wrote this article described what he did next with this K8s cluster. Probably nothing.

Author here --

Something like this? https://www.imore.com/mac-mini-mame-arcade-cabinet-project (Looks cool! Some time down the line I'll have to try it out)

The first thing I did with the setup was to learn about the differences between Helm 2 and Helm 3. I had used Helm 2 in my previous job and wanted to get some hands-on experience with the latest version by installing and modifying some helm charts.

This is certainly something that could be accomplished with a similar setup running locally on my primary computer, but I like the reduced (mental) activation energy of always having it ready to go.

Re: Converting an old MacBook into an always-on personal Kubernetes cluster

#97

Post by spalas »

teejmya wrote: post #93
fortran77 wrote: post #90

I've had bad luck keeping laptops powered 24/7 for months or years. The battery always swells and fails.

Yes, this is inevitable if you're going to run this plugged in over a significant amount of time. Should remove the battery. I found no mention of this in the article, which I think is dangerous. Unfortunately I didn't find any way to contact the author on his site (except an unused comment plugin).

Hi -- Author here.

Thanks for the word of warning. I'll take a look at removing the battery to avoid any issues.

Re: Converting an old MacBook into an always-on personal Kubernetes cluster

#98

Post by ogre_codes »

yayr wrote: post #48
mosselman wrote: post #23

You could sell the MacBook and build a decent raspberrypi cluster with the money you make on it.

except it may not easily survive a power outage

Power outages aren't common enough here that this is a big concern. And since the network is likely to be down, there is likely zero point in keeping your server online. (Your services can survive a reboot cycle right?)

If the services are required to be online, it's likely you'd want your network online as well so you'll need a battery backup for your router. So you run the Raspberry Pi on the same battery backup you have your router on.

Re: Converting an old MacBook into an always-on personal Kubernetes cluster

#99

Post by vernie »

dillonmckay wrote: post #57
mosselman wrote: post #23

You could sell the MacBook and build a decent raspberrypi cluster with the money you make on it.

Would you not want to stay with an Intel-based CPU? https://hackernoon.com/diy-kubernetes-cluster-with-x86-stick...

Why?

Re: Converting an old MacBook into an always-on personal Kubernetes cluster

#100

Post by yjftsjthsd-h »

tsm212 wrote: post #31
akiselev wrote: post #18

Earlier quoted context omitted.

Dual booting/VMs might not be practical or worth the effort if you're a gamer or work in one of these fields: mechanical/electrical engineering, firmware, lab or factory automation, architecture, etc.

I guess the only limiting factor in dual booting would be a lack of skill to set up dual boot. It's quite intimidating at first. I have been dual-booting for ~8 years and I have had my fair share of blunders but nowadays setting up a dual boot pc is very easy especially for the tech savvy (people who are running a k8 cluster) people. I cannot even recall if there was any time where I could restore atleast windows par…

I don't think it's just a skill thing; multibooting is more surface for "interesting" bugs and annoyances as you force interactions between systems that weren't designed to work together. Sure, you might know how to fix Windows overwriting the bootloader for the nth time, but it's still a hassle. Yes, you know how to get the UEFI settings the way you want them, but if you were single-booting the system would have done it for you. I get that it's not that bad once you're used to it, but there is a cost to these things.
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