Posts for: #Tech

OpenShift and CNV: MAC address management in CNV 2.4

This is part of a series of posts about my experience working with OpenShift and CNV. In this post, I’ll look at how the recently released CNV 2.4 resolves some issues in managing virtual machines that are attached directly to local layer 2 networks

In an earlier post, I discussed some issues around the management of virtual machine MAC addresses in CNV 2.3: in particular, that virtual machines are assigned a random MAC address not just at creation time but every time they boot. CNV 2.4 (re-)introduces MAC address pools to alleviate these issues. The high level description reads:

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OpenShift and CNV: Exposing virtualized services

This is the second in a series of posts about my experience working with OpenShift and CNV. In this post, I’ll be taking a look at how to expose services on a virtual machine once you’ve git it up and running.

TL;DR

Networking seems to be a weak area for CNV right now. Out of the box, your options for exposing a service on a virtual machine on a public address at a well known port are slim.

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OpenShift and CNV: Installer network requirements

This is the first in a series of posts about my experience working with OpenShift and CNV (“Container Native Virtualization”, a technology that allows you to use OpenShift to manage virtualized workloads in addition to the containerized workloads for which OpenShift is known). In this post, I’ll be taking a look at the installation experience, and in particular at how restrictions in our local environment interacted with the network requirements of the installer.

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Grove Beginner Kit for Arduino (part 2): First look

The folks at Seeed Studio were kind enough to send me a Grove Beginner Kit for Arduino for review. That’s a mouthful of a name for a compact little kit!

The Grove Beginner Kit for Arduino (henceforth “the Kit”, because ain’t nobody got time to type that out more than a few times in a single article) is about 8.5 x 5 x 1 inches. Closed, you could fit two of them on a piece of 8.5x11 paper with a little room leftover.

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Grove Beginner Kit for Arduino (part 1)

The folks at Seeed Studio have just released the Grove Beginner Kit for Arduino, and they asked if I would be willing to take a look at it in exchange for a free kit. At first glance it reminds me of the Radio Shack (remember when they were cool?) electronics kit I had when I was a kid – but somewhat more advanced. I’m excited to take a closer look, but given shipping these days means it’s probably a month away at least.

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Some thoughts on Mechanical Keyboards

Since we’re all stuck in the house and working from home these days, I’ve had to make some changes to my home office. One change in particular was requested by my wife, who now shares our rather small home office space with me: after a week or so of calls with me clattering away on my old Das Keyboard 3 Professional in the background, she asked if I could get something that was maybe a little bit quieter.

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I see you have the machine that goes ping…

We’re all looking for ways to keep ourselves occupied these days, and for me that means leaping at the chance to turn a small problem into a slightly ridiculous electronics project. For reasons that I won’t go into here I wanted to generate an alert when a certain WiFi BSSID becomes visible. A simple solution to this problem would have been a few lines of shell script to send me an email…but this article isn’t about simple solutions!

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A passwordless serial console for your Raspberry Pi

legendre on #raspbian asked:

How can i config rasp lite to open a shell on the serial uart on boot? Params are 1200-8-N-1 Dont want login running, just straight to sh

In this article, we’ll walk through one way of implementing this configuration.

Activate the serial port

Raspberry Pi OS automatically starts a getty on the serial port if one is available. You should see an agetty process associated with your serial port when you run ps -ef. For example:

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Configuring Open vSwitch with nmcli

I recently acquired a managed switch for my home office in order to segment a few devices off onto their own isolated vlan. As part of this, I want to expose these vlans on my desktop using Open vSwitch (OVS), and I wanted to implement the configuration using NetworkManager rather than either relying on the legacy /etc/sysconfig/network-scripts scripts or rolling my own set of services. These are my notes in case I ever have to do this again.

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How long is a cold spell in Boston?

We’ve had some wacky weather recently. In the space of a week, the temperature went from a high of about 75°F to a low around 15°F. This got me to thinking about what constitutes “normal” weather here in the Boston area, and in particular, how common it is to have a string of consecutive days in which the high temperature stays below freezing. While this was an interesting question in itself, it also seemed like a great opportunity to learn a little about Pandas, the Python data analysis framework.

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