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+<?xml version="1.0" encoding="utf-8"?>
+<feed xmlns="http://www.w3.org/2005/Atom">
+    <updated>2025-02-21T11:13:36+02:00</updated>
+    <title>foo.zone feed</title>
+    <subtitle>To be in the .zone!</subtitle>
+    <link href="gemini://foo.zone/gemfeed/atom.xml" rel="self" />
+    <link href="gemini://foo.zone/" />
+    <id>gemini://foo.zone/</id>
+    <entry>
+        <title>Random Weird Things - Part Ⅱ</title>
+        <link href="gemini://foo.zone/gemfeed/2025-02-08-random-weird-things-ii.gmi" />
+        <id>gemini://foo.zone/gemfeed/2025-02-08-random-weird-things-ii.gmi</id>
+        <updated>2025-02-08T11:06:16+02:00</updated>
+        <author>
+            <name>Paul Buetow aka snonux</name>
+            <email>paul@dev.buetow.org</email>
+        </author>
+        <summary>Every so often, I come across random, weird, and unexpected things on the internet. I thought it would be neat to share them here from time to time. This is the second run.</summary>
+        <content type="xhtml">
+            <div xmlns="http://www.w3.org/1999/xhtml">
+                <h1 style='display: inline' id='random-weird-things---part-'>Random Weird Things - Part Ⅱ</h1><br />
+<br />
+<span class='quote'>Published at 2025-02-08T11:06:16+02:00</span><br />
+<br />
+<span>Every so often, I come across random, weird, and unexpected things on the internet. I thought it would be neat to share them here from time to time. This is the second run.</span><br />
+<br />
+<a class='textlink' href='./2024-07-05-random-weird-things.html'>2024-07-05 Random Weird Things - Part Ⅰ</a><br />
+<a class='textlink' href='./2025-02-08-random-weird-things-ii.html'>2025-02-08 Random Weird Things - Part Ⅱ (You are currently reading this)</a><br />
+<br />
+<pre>
+/\_/\           /\_/\
+( o.o ) WHOA!! ( o.o )
+&gt; ^ &lt;           &gt; ^ &lt;
+/   \    MOEEW! /   \
+/______\       /______\
+</pre>
+<br />
+<h2 style='display: inline' id='table-of-contents'>Table of Contents</h2><br />
+<br />
+<ul>
+<li><a href='#random-weird-things---part-'>Random Weird Things - Part Ⅱ</a></li>
+<li>⇢ <a href='#11-the-sqlite-codebase-is-a-gem'>11. The SQLite codebase is a gem</a></li>
+<li>⇢ <a href='#go-programming'>Go Programming</a></li>
+<li>⇢ ⇢ <a href='#12-official-go-font'>12. Official Go font</a></li>
+<li>⇢ ⇢ <a href='#13-go-functions-can-have-methods'>13. Go functions can have methods</a></li>
+<li>⇢ <a href='#macos'>macOS</a></li>
+<li>⇢ ⇢ <a href='#14--and-ss-are-treated-the-same'>14. ß and ss are treated the same</a></li>
+<li>⇢ ⇢ <a href='#15-colon-as-file-path-separator'>15. Colon as file path separator</a></li>
+<li>⇢ <a href='#16-polyglots---programs-written-in-multiple-languages'>16. Polyglots - programs written in multiple languages</a></li>
+<li>⇢ <a href='#17-languages-where-indices-start-at-1'>17. Languages, where indices start at 1</a></li>
+<li>⇢ <a href='#18-perl-poetry'>18. Perl Poetry</a></li>
+<li>⇢ <a href='#19-css3-is-turing-complete'>19. CSS3 is turing complete</a></li>
+<li>⇢ <a href='#20-the-biggest-shell-programs-'>20. The biggest shell programs </a></li>
+</ul><br />
+<h2 style='display: inline' id='11-the-sqlite-codebase-is-a-gem'>11. The SQLite codebase is a gem</h2><br />
+<br />
+<span>Check this out:</span><br />
+<br />
+<a href='./random-weird-things-ii/sqlite-gem.png'><img alt='SQLite Gem' title='SQLite Gem' src='./random-weird-things-ii/sqlite-gem.png' /></a><br />
+<br />
+<span>Source:</span><br />
+<br />
+<a class='textlink' href='https://wetdry.world/@memes/112717700557038278'>https://wetdry.world/@memes/112717700557038278</a><br />
+<br />
+<h2 style='display: inline' id='go-programming'>Go Programming</h2><br />
+<br />
+<h3 style='display: inline' id='12-official-go-font'>12. Official Go font</h3><br />
+<br />
+<span>The Go programming language has an official font called "Go Font." It was created to complement the aesthetic of the Go language, ensuring clear and legible rendering of code. The font includes a monospace version for code and a proportional version for general text, supporting consistent look and readability in Go-related materials and development environments. </span><br />
+<br />
+<span>Check out some Go code displayed using the Go font:</span><br />
+<br />
+<a href='./random-weird-things-ii/go-font-code.png'><img alt='Go font code' title='Go font code' src='./random-weird-things-ii/go-font-code.png' /></a><br />
+<br />
+<a class='textlink' href='https://go.dev/blog/go-fonts'>https://go.dev/blog/go-fonts</a><br />
+<br />
+<span>The design emphasizes simplicity and readability, reflecting Go&#39;s philosophy of clarity and efficiency.</span><br />
+<br />
+<span>I found it interesting and/or weird, as Go is a programming language. Why should it bother having its own font? I have never seen another open-source project like Go do this. But I also like it. Maybe I will use it in the future for this blog :-) </span><br />
+<br />
+<h3 style='display: inline' id='13-go-functions-can-have-methods'>13. Go functions can have methods</h3><br />
+<br />
+<span>Functions on struct types? Well, know. Functions on types like <span class='inlinecode'>int</span> and <span class='inlinecode'>string</span>? It&#39;s also known of, but a bit lesser. Functions on function types? That sounds a bit funky, but it&#39;s possible, too! For demonstration, have a look at this snippet:</span><br />
+<br />
+<!-- Generator: GNU source-highlight 3.1.9
+by Lorenzo Bettini
+http://www.lorenzobettini.it
+http://www.gnu.org/software/src-highlite -->
+<pre><b><u><font color="#000000">package</font></u></b> main
+
+<b><u><font color="#000000">import</font></u></b> <font color="#808080">"log"</font>
+
+<b><u><font color="#000000">type</font></u></b> fun <b><u><font color="#000000">func</font></u></b>() <b><font color="#000000">string</font></b>
+
+<b><u><font color="#000000">func</font></u></b> (f fun) Bar() <b><font color="#000000">string</font></b> {
+        <b><u><font color="#000000">return</font></u></b> <font color="#808080">"Bar"</font>
+}
+
+<b><u><font color="#000000">func</font></u></b> main() {
+        <b><u><font color="#000000">var</font></u></b> f fun = <b><u><font color="#000000">func</font></u></b>() <b><font color="#000000">string</font></b> {
+                <b><u><font color="#000000">return</font></u></b> <font color="#808080">"Foo"</font>
+        }
+        log.Println(<font color="#808080">"Example 1: "</font>, f())
+        log.Println(<font color="#808080">"Example 2: "</font>, f.Bar())
+        log.Println(<font color="#808080">"Example 3: "</font>, fun(f.Bar).Bar())
+        log.Println(<font color="#808080">"Example 4: "</font>, fun(fun(f.Bar).Bar).Bar())
+}
+</pre>
+<br />
+<span>It runs just fine:</span><br />
+<br />
+<!-- Generator: GNU source-highlight 3.1.9
+by Lorenzo Bettini
+http://www.lorenzobettini.it
+http://www.gnu.org/software/src-highlite -->
+<pre>❯ go run main.go
+<font color="#000000">2025</font>/<font color="#000000">02</font>/<font color="#000000">07</font> <font color="#000000">22</font>:<font color="#000000">56</font>:<font color="#000000">14</font> Example <font color="#000000">1</font>:  Foo
+<font color="#000000">2025</font>/<font color="#000000">02</font>/<font color="#000000">07</font> <font color="#000000">22</font>:<font color="#000000">56</font>:<font color="#000000">14</font> Example <font color="#000000">2</font>:  Bar
+<font color="#000000">2025</font>/<font color="#000000">02</font>/<font color="#000000">07</font> <font color="#000000">22</font>:<font color="#000000">56</font>:<font color="#000000">14</font> Example <font color="#000000">3</font>:  Bar
+<font color="#000000">2025</font>/<font color="#000000">02</font>/<font color="#000000">07</font> <font color="#000000">22</font>:<font color="#000000">56</font>:<font color="#000000">14</font> Example <font color="#000000">4</font>:  Bar
+</pre>
+<br />
+<h2 style='display: inline' id='macos'>macOS</h2><br />
+<br />
+<span>For personal computing, I don&#39;t use Apple, but I have to use it for work. </span><br />
+<br />
+<h3 style='display: inline' id='14--and-ss-are-treated-the-same'>14. ß and ss are treated the same</h3><br />
+<br />
+<span>Know German? In German, the letter "sarp s" is written as ß. ß is treated the same as ss on macOS.</span><br />
+<br />
+<span>On a case-insensitive file system like macOS, not only are uppercase and lowercase letters treated the same, but non-Latin characters like the German "ß" are also considered equivalent to their Latin counterparts (in this case, "ss").</span><br />
+<br />
+<span>So, even though "Maß" and "Mass" are not strictly equivalent, the macOS file system still treats them as the same filename due to its handling of Unicode characters. This can sometimes lead to unexpected behaviour. Check this out:</span><br />
+<br />
+<!-- Generator: GNU source-highlight 3.1.9
+by Lorenzo Bettini
+http://www.lorenzobettini.it
+http://www.gnu.org/software/src-highlite -->
+<pre>❯ touch Maß
+❯ ls -l
+-rw-r--r--@ <font color="#000000">1</font> paul  wheel  <font color="#000000">0</font> Feb  <font color="#000000">7</font> <font color="#000000">23</font>:<font color="#000000">02</font> Maß
+❯ touch Mass
+❯ ls -l
+-rw-r--r--@ <font color="#000000">1</font> paul  wheel  <font color="#000000">0</font> Feb  <font color="#000000">7</font> <font color="#000000">23</font>:<font color="#000000">02</font> Maß
+❯ rm Mass
+❯ ls -l
+
+❯ touch Mass
+❯ ls -ltr
+-rw-r--r--@ <font color="#000000">1</font> paul  wheel  <font color="#000000">0</font> Feb  <font color="#000000">7</font> <font color="#000000">23</font>:<font color="#000000">02</font> Mass
+❯ rm Maß
+❯ ls -l
+
+</pre>
+<br />
+<h3 style='display: inline' id='15-colon-as-file-path-separator'>15. Colon as file path separator</h3><br />
+<br />
+<span>MacOS can use the colon as a file path separator on its ADFS (file system). A typical ADFS file pathname on a hard disc might be:</span><br />
+<br />
+<pre>
+ADFS::4.$.Documents.Techwriter.Myfile
+</pre>
+<br />
+<span>I can&#39;t reproduce this on my (work) Mac, though, as it now uses the APFS file system. In essence, ADFS is an older file system, while APFS is a contemporary file system optimized for Apple&#39;s modern devices.</span><br />
+<br />
+<a class='textlink' href='https://social.jvns.ca/@b0rk/113041293527832730'>https://social.jvns.ca/@b0rk/113041293527832730</a><br />
+<br />
+<h2 style='display: inline' id='16-polyglots---programs-written-in-multiple-languages'>16. Polyglots - programs written in multiple languages</h2><br />
+<br />
+<span>A coding polyglot is a program or script written so that it can be executed in multiple programming languages without modification. This is typically achieved by leveraging syntax overlaps or crafting valid and meaningful code in each targeted language. Polyglot programs are often created as a challenge or for demonstration purposes to showcase language similarities or clever coding techniques.</span><br />
+<br />
+<span>Check out my very own polyglot:</span><br />
+<br />
+<a class='textlink' href='./2014-03-24-the-fibonacci.pl.c-polyglot.html'>The <span class='inlinecode'>fibonatti.pl.c</span> Polyglot</a><br />
+<br />
+<h2 style='display: inline' id='17-languages-where-indices-start-at-1'>17. Languages, where indices start at 1</h2><br />
+<br />
+<span>Array indices start at 1 instead of 0 in some programming languages, known as one-based indexing. This can be controversial because zero-based indexing is more common in popular languages like C, C++, Java, and Python. One-based indexing can lead to off-by-one errors when developers switch between languages with different indexing schemes.</span><br />
+<br />
+<span>Languages with One-Based Indexing:</span><br />
+<br />
+<ul>
+<li>Fortran</li>
+<li>MATLAB</li>
+<li>Lua</li>
+<li>R (for vectors and lists)</li>
+<li>Smalltalk</li>
+<li>Julia (by default, although zero-based indexing is also possible)</li>
+</ul><br />
+<span><span class='inlinecode'>foo.lua</span> example:</span><br />
+<br />
+<!-- Generator: GNU source-highlight 3.1.9
+by Lorenzo Bettini
+http://www.lorenzobettini.it
+http://www.gnu.org/software/src-highlite -->
+<pre>arr = {<font color="#000000">10</font>, <font color="#000000">20</font>, <font color="#000000">30</font>, <font color="#000000">40</font>, <font color="#000000">50</font>}
+print(arr[<font color="#000000">1</font>]) <i><font color="silver">-- Accessing the first element</font></i>
+</pre>
+<br />
+<!-- Generator: GNU source-highlight 3.1.9
+by Lorenzo Bettini
+http://www.lorenzobettini.it
+http://www.gnu.org/software/src-highlite -->
+<pre>❯ lua foo.lua
+<font color="#000000">10</font>
+</pre>
+<br />
+<span>One-based indexing is more natural for human-readable, mathematical, and theoretical contexts, where counting traditionally starts from one.</span><br />
+<br />
+<h2 style='display: inline' id='18-perl-poetry'>18. Perl Poetry</h2><br />
+<br />
+<span>Perl Poetry is a playful and creative practice within the programming community where Perl code is written as a poem. These poems are crafted to be syntactically valid Perl code and make sense as poetic text, often with whimsical or humorous intent. This showcases Perl&#39;s flexibility and expressiveness, as well as the creativity of its programmers.</span><br />
+<br />
+<span>See this Poetry of my own; the Perl interpreter does not yield any syntax error parsing that. But also, the Peom doesn&#39;t do anything useful then executed:</span><br />
+<br />
+<!-- Generator: GNU source-highlight 3.1.9
+by Lorenzo Bettini
+http://www.lorenzobettini.it
+http://www.gnu.org/software/src-highlite -->
+<pre><i><font color="silver"># (C) 2006 by Paul C. Buetow</font></i>
+
+Christmas:{time;<i><font color="silver">#!!!</font></i>
+
+Children: <b><u><font color="#000000">do</font></u></b> <b><u><font color="#000000">tell</font></u></b> $wishes;
+
+Santa: <b><u><font color="#000000">for</font></u></b> $each (@children) { 
+BEGIN { <b><u><font color="#000000">read</font></u></b> $each, $their, wishes <b><u><font color="#000000">and</font></u></b> study them; <b><u><font color="#000000">use</font></u></b> Memoize<i><font color="silver">#ing</font></i>
+
+} <b><u><font color="#000000">use</font></u></b> constant gift, <font color="#808080">'wrapping'</font>; 
+<b><u><font color="#000000">package</font></u></b> Gifts; <b><u><font color="#000000">pack</font></u></b> $each, gift <b><u><font color="#000000">and</font></u></b> <b><u><font color="#000000">bless</font></u></b> $each <b><u><font color="#000000">and</font></u></b> <b><u><font color="#000000">goto</font></u></b> deliver
+or <b><u><font color="#000000">do</font></u></b> <b><u><font color="#000000">import</font></u></b> <b><u><font color="#000000">if</font></u></b> not <b><u><font color="#000000">local</font></u></b> $available,!!! HO, HO, HO;
+
+<b><u><font color="#000000">redo</font></u></b> Santa, <b><u><font color="#000000">pipe</font></u></b> $gifts, to_childs;
+<b><u><font color="#000000">redo</font></u></b> Santa <b><u><font color="#000000">and</font></u></b> <b><u><font color="#000000">do</font></u></b> <b><u><font color="#000000">return</font></u></b> <b><u><font color="#000000">if</font></u></b> <b><u><font color="#000000">last</font></u></b> one, is, delivered; 
+
+deliver: gift <b><u><font color="#000000">and</font></u></b> <b><u><font color="#000000">require</font></u></b> diagnostics <b><u><font color="#000000">if</font></u></b> <b><u><font color="#000000">our</font></u></b> $gifts ,not break;
+<b><u><font color="#000000">do</font></u></b>{ <b><u><font color="#000000">use</font></u></b> NEXT; time; <b><u><font color="#000000">tied</font></u></b> $gifts} <b><u><font color="#000000">if</font></u></b> broken <b><u><font color="#000000">and</font></u></b> <b><u><font color="#000000">dump</font></u></b> the, broken, ones;
+The_children: <b><u><font color="#000000">sleep</font></u></b> <b><u><font color="#000000">and</font></u></b> <b><u><font color="#000000">wait</font></u></b> <b><u><font color="#000000">for</font></u></b> (<b><u><font color="#000000">each</font></u></b> %gift) <b><u><font color="#000000">and</font></u></b> try { to =&gt; <b><u><font color="#000000">untie</font></u></b> $gifts };
+
+<b><u><font color="#000000">redo</font></u></b> Santa, <b><u><font color="#000000">pipe</font></u></b> $gifts, to_childs;
+<b><u><font color="#000000">redo</font></u></b> Santa <b><u><font color="#000000">and</font></u></b> <b><u><font color="#000000">do</font></u></b> <b><u><font color="#000000">return</font></u></b> <b><u><font color="#000000">if</font></u></b> <b><u><font color="#000000">last</font></u></b> one, is, delivered; 
+
+The_christmas_tree: formline <b><u><font color="#000000">s</font></u></b><font color="#808080">/ /childrens/</font>, $gifts;
+<b><u><font color="#000000">alarm</font></u></b> <b><u><font color="#000000">and</font></u></b> <b><u><font color="#000000">warn</font></u></b> <b><u><font color="#000000">if</font></u></b> not <b><u><font color="#000000">exists</font></u></b> $Christmas{ tree}, @t, $ENV{HOME};  
+<b><u><font color="#000000">write</font></u></b> &lt;&lt;EMail
+ to the parents to buy a new christmas tree!!!!<font color="#000000">111</font>
+ <b><u><font color="#000000">and</font></u></b> send the
+EMail
+;<b><u><font color="#000000">wait</font></u></b> <b><u><font color="#000000">and</font></u></b> <b><u><font color="#000000">redo</font></u></b> deliver until <b><u><font color="#000000">defined</font></u></b> <b><u><font color="#000000">local</font></u></b> $tree;
+
+<b><u><font color="#000000">redo</font></u></b> Santa, <b><u><font color="#000000">pipe</font></u></b> $gifts, to_childs;
+<b><u><font color="#000000">redo</font></u></b> Santa <b><u><font color="#000000">and</font></u></b> <b><u><font color="#000000">do</font></u></b> <b><u><font color="#000000">return</font></u></b> <b><u><font color="#000000">if</font></u></b> <b><u><font color="#000000">last</font></u></b> one, is, delivered ;}
+
+END {} <b><u><font color="#000000">our</font></u></b> $mission <b><u><font color="#000000">and</font></u></b> <b><u><font color="#000000">do</font></u></b> <b><u><font color="#000000">sleep</font></u></b> until <b><u><font color="#000000">next</font></u></b> Christmas ;}
+
+__END__
+
+This is perl, v5.<font color="#000000">8.8</font> built <b><u><font color="#000000">for</font></u></b> i386-freebsd-64int
+</pre>
+<br />
+<a class='textlink' href='./2008-06-26-perl-poetry.html'>More Perl Poetry of mine</a><br />
+<br />
+<h2 style='display: inline' id='19-css3-is-turing-complete'>19. CSS3 is turing complete</h2><br />
+<br />
+<span>CSS3 is Turing complete because it can simulate a Turing machine using only CSS animations and styles without any JavaScript or external logic. This is achieved by using keyframe animations to change the styles of HTML elements in a way that encodes computation, performing calculations and state transitions. </span><br />
+<br />
+<a class='textlink' href='https://stackoverflow.com/questions/2497146/is-css-turing-complete'>Is CSS turing complete?</a><br />
+<br />
+<span>It is surprising because CSS is primarily a styling language intended for the presentation layer of web pages, not for computation or logic. Its capability to perform complex computations defies its typical use case and showcases the unintended computational power that can emerge from the creative use of seemingly straightforward technologies.</span><br />
+<br />
+<span>Check out this 100% CSS implementation of the Conways Game of Life:</span><br />
+<br />
+<a href='./random-weird-things-ii/css-conway.png'><img src='./random-weird-things-ii/css-conway.png' /></a><br />
+<br />
+<a class='textlink' href='https://github.com/propjockey/css-conways-game-of-life'>CSS Conways Game of Life</a><br />
+<br />
+<span>Conway&#39;s Game of Life is Turing complete because it can simulate a universal Turing machine, meaning it can perform any computation that a computer can, given the right initial conditions and sufficient time and space. Suppose a language can implement Conway&#39;s Game of Life. In that case, it demonstrates the language&#39;s ability to handle complex state transitions and computations. It has the necessary constructs (like iteration, conditionals, and data manipulation) to simulate any algorithm, thus confirming its Turing completeness.</span><br />
+<br />
+<h2 style='display: inline' id='20-the-biggest-shell-programs-'>20. The biggest shell programs </h2><br />
+<br />
+<span>One would think that shell scripts are only suitable for small tasks. Well, I must be wrong, as there are huge shell programs out there (up to 87k LOC) which aren&#39;t auto-generated but hand-written!</span><br />
+<br />
+<a class='textlink' href='https://github.com/oils-for-unix/oils/wiki/The-Biggest-Shell-Programs-in-the-World'>The Biggest Sell Programs in the World</a><br />
+<br />
+<span>My Gemtexter (bash) is only 1329 LOC as of now. So it&#39;s tiny.</span><br />
+<br />
+<a class='textlink' href='./2021-06-05-gemtexter-one-bash-script-to-rule-it-all.html'>Gemtexter - One Bash script to rule it all</a><br />
+<br />
+<span>I hope you had some fun. E-Mail your comments to <span class='inlinecode'>paul@nospam.buetow.org</span> :-)</span><br />
+<br />
+<a class='textlink' href='../'>Back to the main site</a><br />
+            </div>
+        </content>
+    </entry>
+    <entry>
+        <title>f3s: Kubernetes with FreeBSD - Part 3: Protecting from power cuts</title>
+        <link href="gemini://foo.zone/gemfeed/2025-02-01-f3s-kubernetes-with-freebsd-part-3.gmi" />
+        <id>gemini://foo.zone/gemfeed/2025-02-01-f3s-kubernetes-with-freebsd-part-3.gmi</id>
+        <updated>2025-01-30T09:22:06+02:00</updated>
+        <author>
+            <name>Paul Buetow aka snonux</name>
+            <email>paul@dev.buetow.org</email>
+        </author>
+        <summary>This is the third blog post about my f3s series for my self-hosting demands in my home lab. f3s? The 'f' stands for FreeBSD, and the '3s' stands for k3s, the Kubernetes distribution we will use on FreeBSD-based physical machines.</summary>
+        <content type="xhtml">
+            <div xmlns="http://www.w3.org/1999/xhtml">
+                <h1 style='display: inline' id='f3s-kubernetes-with-freebsd---part-3-protecting-from-power-cuts'>f3s: Kubernetes with FreeBSD - Part 3: Protecting from power cuts</h1><br />
+<br />
+<span class='quote'>Published at 2025-01-30T09:22:06+02:00</span><br />
+<br />
+<span>This is the third blog post about my f3s series for my self-hosting demands in my home lab. f3s? The "f" stands for FreeBSD, and the "3s" stands for k3s, the Kubernetes distribution we will use on FreeBSD-based physical machines.</span><br />
+<br />
+<a class='textlink' href='./2024-11-17-f3s-kubernetes-with-freebsd-part-1.html'>2024-11-17 f3s: Kubernetes with FreeBSD - Part 1: Setting the stage</a><br />
+<a class='textlink' href='./2024-12-03-f3s-kubernetes-with-freebsd-part-2.html'>2024-12-03 f3s: Kubernetes with FreeBSD - Part 2: Hardware and base installation</a><br />
+<a class='textlink' href='./2025-02-01-f3s-kubernetes-with-freebsd-part-3.html'>2025-02-01 f3s: Kubernetes with FreeBSD - Part 3: Protecting from power cuts (You are currently reading this)</a><br />
+<br />
+<a href='./f3s-kubernetes-with-freebsd-part-1/f3slogo.png'><img alt='f3s logo' title='f3s logo' src='./f3s-kubernetes-with-freebsd-part-1/f3slogo.png' /></a><br />
+<br />
+<h2 style='display: inline' id='table-of-contents'>Table of Contents</h2><br />
+<br />
+<ul>
+<li><a href='#f3s-kubernetes-with-freebsd---part-3-protecting-from-power-cuts'>f3s: Kubernetes with FreeBSD - Part 3: Protecting from power cuts</a></li>
+<li>⇢ <a href='#introduction'>Introduction</a></li>
+<li>⇢ <a href='#changes-since-last-time'>Changes since last time</a></li>
+<li>⇢ ⇢ <a href='#freebsd-upgrade-from-141-to-142'>FreeBSD upgrade from 14.1 to 14.2</a></li>
+<li>⇢ ⇢ <a href='#a-new-home-behind-the-tv'>A new home (behind the TV)</a></li>
+<li>⇢ <a href='#the-ups-hardware'>The UPS hardware</a></li>
+<li>⇢ <a href='#configuring-freebsd-to-work-with-the-ups'>Configuring FreeBSD to Work with the UPS</a></li>
+<li>⇢ ⇢ <a href='#usb-device-detection'>USB Device Detection</a></li>
+<li>⇢ ⇢ <a href='#apcupsd-installation'><span class='inlinecode'>apcupsd</span> Installation</a></li>
+<li>⇢ ⇢ <a href='#ups-connectivity-test'>UPS Connectivity Test</a></li>
+<li>⇢ <a href='#apc-info-on-partner-nodes'>APC Info on Partner Nodes:</a></li>
+<li>⇢ ⇢ <a href='#installation-on-partners'>Installation on partners</a></li>
+<li>⇢ <a href='#power-outage-simulation'>Power outage simulation</a></li>
+<li>⇢ ⇢ <a href='#pulling-the-plug'>Pulling the plug</a></li>
+<li>⇢ ⇢ <a href='#restoring-power'>Restoring power</a></li>
+</ul><br />
+<h2 style='display: inline' id='introduction'>Introduction</h2><br />
+<br />
+<span>In this blog post, we are setting up the UPS for the cluster. A UPS, or Uninterruptible Power Supply, safeguards my cluster from unexpected power outages and surges. It acts as a backup battery that kicks in when the electricity cuts out—especially useful in my area, where power cuts are frequent—allowing for a graceful system shutdown and preventing data loss and corruption. This is especially important since I will also store some of my data on the f3s nodes.</span><br />
+<br />
+<h2 style='display: inline' id='changes-since-last-time'>Changes since last time</h2><br />
+<br />
+<h3 style='display: inline' id='freebsd-upgrade-from-141-to-142'>FreeBSD upgrade from 14.1 to 14.2</h3><br />
+<br />
+<span>There has been a new release since the last blog post in this series. The upgrade from 14.1 was as easy as:</span><br />
+<br />
+<!-- Generator: GNU source-highlight 3.1.9
+by Lorenzo Bettini
+http://www.lorenzobettini.it
+http://www.gnu.org/software/src-highlite -->
+<pre>paul@f0: ~ % doas freebsd-update fetch
+paul@f0: ~ % doas freebsd-update install
+paul@f0: ~ % doas freebsd-update -r <font color="#000000">14.2</font>-RELEASE upgrade
+paul@f0: ~ % doas freebsd-update install
+paul@f0: ~ % doas shutdown -r now
+</pre>
+<br />
+<span>And after rebooting, I ran:</span><br />
+<br />
+<!-- Generator: GNU source-highlight 3.1.9
+by Lorenzo Bettini
+http://www.lorenzobettini.it
+http://www.gnu.org/software/src-highlite -->
+<pre>paul@f0: ~ % doas freebsd-update install
+paul@f0: ~ % doas pkg update
+paul@f0: ~ % doas pkg upgrade
+paul@f0: ~ % doas shutdown -r now
+</pre>
+<br />
+<span>And after another reboot, I was on 14.2:</span><br />
+<br />
+<!-- Generator: GNU source-highlight 3.1.9
+by Lorenzo Bettini
+http://www.lorenzobettini.it
+http://www.gnu.org/software/src-highlite -->
+<pre>paul@f0:~ % uname -a
+FreeBSD f0.lan.buetow.org <font color="#000000">14.2</font>-RELEASE FreeBSD <font color="#000000">14.2</font>-RELEASE 
+ releng/<font color="#000000">14.2</font>-n<font color="#000000">269506</font>-c8918d6c7412 GENERIC amd64
+</pre>
+<br />
+<span>And, of course, I ran this on all 3 nodes!</span><br />
+<br />
+<h3 style='display: inline' id='a-new-home-behind-the-tv'>A new home (behind the TV)</h3><br />
+<br />
+<span>I&#39;ve put all the infrastructure behind my TV, as plenty of space is available. The TV hides most of the setup, which drastically improved the SAF (spouse acceptance factor).</span><br />
+<br />
+<a href='./f3s-kubernetes-with-freebsd-part-3/f3s-changes.jpg'><img alt='New hardware placement arrangement' title='New hardware placement arrangement' src='./f3s-kubernetes-with-freebsd-part-3/f3s-changes.jpg' /></a><br />
+<br />
+<span>I got rid of the mini-switch I mentioned in the previous blog post. I have the TP-Link EAP615-Wall mounted on the wall nearby, which is my OpenWrt-powered Wi-Fi hotspot. It also has 3 Ethernet ports, to which I connected the Beelink nodes. That&#39;s the device you see at the very top.</span><br />
+<br />
+<span>The Ethernet cables go downward through the cable boxes to the Beelink nodes. In addition to the Beelink f3s nodes, I connected the TP-Link to the UPS as well (not discussed further in this blog post, but the positive side effect is that my Wi-Fi will still work during a power loss for some time—and during a power cut, the Beelink nodes will still be able to communicate with each other).</span><br />
+<br />
+<span>On the very left (the black box) is the UPS, with four power outlets. Three go to the Beelink nodes, and one goes to the TP-Link. A USB output is also connected to the first Beelink node, <span class='inlinecode'>f0</span>. </span><br />
+<br />
+<span>On the very right (halfway hidden behind the TV) are the 3 Beelink nodes stacked on top of each other. The only downside (or upside?) is that my 14-month-old daughter is now chaos-testing the Beelink nodes, as the red power buttons (now reachable for her) are very attractive for her to press when passing by randomly. :-) Luckily, that will only cause graceful system shutdowns!</span><br />
+<br />
+<h2 style='display: inline' id='the-ups-hardware'>The UPS hardware</h2><br />
+<br />
+<span>I wanted a UPS that I could connect to via FreeBSD, and that would provide enough backup power to operate the cluster for a couple of minutes (it turned out to be around an hour, but this time will likely be shortened after future hardware upgrades, like additional drives and a backup enclosure) and to automatically initiate the shutdown of all the f3s nodes.</span><br />
+<br />
+<span>I decided on the APC Back-UPS BX750MI model because:</span><br />
+<br />
+<ul>
+<li>Zero noise level when there is no power cut (some light noise when the battery is in operation during a power cut).</li>
+<li>Cost: It is relatively affordable (not costing thousands).</li>
+<li>USB connectivity: Can be connected via USB to one of the FreeBSD hosts to read the UPS status.</li>
+<li>A power output of 750VA (or 410 watts), suitable for an hour of runtime for my f3s nodes (plus the Wi-Fi router).</li>
+<li>Multiple power outlets: Can connect all 3 f3s nodes directly.</li>
+<li>User-replaceable batteries: I can replace the batteries myself after two years or more (depending on usage).</li>
+<li>Its compact design. Overall, I like how it looks.</li>
+</ul><br />
+<a href='./f3s-kubernetes-with-freebsd-part-3/apc-back-ups.jpg'><img alt='The APC Back-UPS BX750MI in operation.' title='The APC Back-UPS BX750MI in operation.' src='./f3s-kubernetes-with-freebsd-part-3/apc-back-ups.jpg' /></a><br />
+<br />
+<h2 style='display: inline' id='configuring-freebsd-to-work-with-the-ups'>Configuring FreeBSD to Work with the UPS</h2><br />
+<br />
+<h3 style='display: inline' id='usb-device-detection'>USB Device Detection</h3><br />
+<br />
+<span>Once plugged in via USB on FreeBSD, I could see the following in the kernel messages:</span><br />
+<br />
+<!-- Generator: GNU source-highlight 3.1.9
+by Lorenzo Bettini
+http://www.lorenzobettini.it
+http://www.gnu.org/software/src-highlite -->
+<pre>paul@f0: ~ % doas dmesg | grep UPS
+ugen0.<font color="#000000">2</font>: &lt;American Power Conversion Back-UPS BX750MI&gt; at usbus0
+</pre>
+<br />
+<h3 style='display: inline' id='apcupsd-installation'><span class='inlinecode'>apcupsd</span> Installation</h3><br />
+<br />
+<span>To make use of the USB connection, the <span class='inlinecode'>apcupsd</span> package had to be installed:</span><br />
+<br />
+<!-- Generator: GNU source-highlight 3.1.9
+by Lorenzo Bettini
+http://www.lorenzobettini.it
+http://www.gnu.org/software/src-highlite -->
+<pre>paul@f0: ~ % doas install apcupsd
+</pre>
+<br />
+<span>I have made the following modifications to the configuration file so that the UPS can be used via the USB interface:</span><br />
+<br />
+<!-- Generator: GNU source-highlight 3.1.9
+by Lorenzo Bettini
+http://www.lorenzobettini.it
+http://www.gnu.org/software/src-highlite -->
+<pre>paul@f0:/usr/local/etc/apcupsd % diff -u apcupsd.conf.sample  apcupsd.conf
+--- apcupsd.conf.sample <font color="#000000">2024</font>-<font color="#000000">11</font>-<font color="#000000">01</font> <font color="#000000">16</font>:<font color="#000000">40</font>:<font color="#000000">42.000000000</font> +<font color="#000000">0200</font>
++++ apcupsd.conf        <font color="#000000">2024</font>-<font color="#000000">12</font>-<font color="#000000">03</font> <font color="#000000">10</font>:<font color="#000000">58</font>:<font color="#000000">24.009501000</font> +<font color="#000000">0200</font>
+@@ -<font color="#000000">31</font>,<font color="#000000">7</font> +<font color="#000000">31</font>,<font color="#000000">7</font> @@
+ <i><font color="silver">#     940-1524C, 940-0024G, 940-0095A, 940-0095B,</font></i>
+ <i><font color="silver">#     940-0095C, 940-0625A, M-04-02-2000</font></i>
+ <i><font color="silver">#</font></i>
+-UPSCABLE smart
++UPSCABLE usb
+
+ <i><font color="silver"># To get apcupsd to work, in addition to defining the cable</font></i>
+ <i><font color="silver"># above, you must also define a UPSTYPE, which corresponds to</font></i>
+@@ -<font color="#000000">88</font>,<font color="#000000">8</font> +<font color="#000000">88</font>,<font color="#000000">10</font> @@
+ <i><font color="silver">#                            that apcupsd binds to that particular unit</font></i>
+ <i><font color="silver">#                            (helpful if you have more than one USB UPS).</font></i>
+ <i><font color="silver">#</font></i>
+-UPSTYPE apcsmart
+-DEVICE /dev/usv
++UPSTYPE usb
++DEVICE
+
+ <i><font color="silver"># POLLTIME &lt;int&gt;</font></i>
+ <i><font color="silver">#   Interval (in seconds) at which apcupsd polls the UPS for status. This</font></i>
+</pre>
+<br />
+<span>I left the remaining settings as the default ones; for example, the following are of main interest:</span><br />
+<br />
+<pre>
+# If during a power failure, the remaining battery percentage
+# (as reported by the UPS) is below or equal to BATTERYLEVEL,
+# apcupsd will initiate a system shutdown.
+BATTERYLEVEL 5
+
+# If during a power failure, the remaining runtime in minutes
+# (as calculated internally by the UPS) is below or equal to MINUTES,
+# apcupsd, will initiate a system shutdown.
+MINUTES 3
+</pre>
+<br />
+<span>I then enabled and started the daemon:</span><br />
+<br />
+<!-- Generator: GNU source-highlight 3.1.9
+by Lorenzo Bettini
+http://www.lorenzobettini.it
+http://www.gnu.org/software/src-highlite -->
+<pre>paul@f0:/usr/local/etc/apcupsd % doas sysrc apcupsd_enable=YES
+apcupsd_enable:  -&gt; YES
+paul@f0:/usr/local/etc/apcupsd % doas service apcupsd start
+Starting apcupsd.
+</pre>
+<br />
+<h3 style='display: inline' id='ups-connectivity-test'>UPS Connectivity Test</h3><br />
+<br />
+<span>And voila, I could now access the UPS information via the <span class='inlinecode'>apcaccess</span> command; how convenient :-) (I also read through the manual page, which provides a good understanding of what else can be done with it!).</span><br />
+<br />
+<!-- Generator: GNU source-highlight 3.1.9
+by Lorenzo Bettini
+http://www.lorenzobettini.it
+http://www.gnu.org/software/src-highlite -->
+<pre>paul@f0:~ % apcaccess
+APC      : <font color="#000000">001</font>,<font color="#000000">035</font>,<font color="#000000">0857</font>
+DATE     : <font color="#000000">2025</font>-<font color="#000000">01</font>-<font color="#000000">26</font> <font color="#000000">14</font>:<font color="#000000">43</font>:<font color="#000000">27</font> +<font color="#000000">0200</font>
+HOSTNAME : f0.lan.buetow.org
+VERSION  : <font color="#000000">3.14</font>.<font color="#000000">14</font> (<font color="#000000">31</font> May <font color="#000000">2016</font>) freebsd
+UPSNAME  : f0.lan.buetow.org
+CABLE    : USB Cable
+DRIVER   : USB UPS Driver
+UPSMODE  : Stand Alone
+STARTTIME: <font color="#000000">2025</font>-<font color="#000000">01</font>-<font color="#000000">26</font> <font color="#000000">14</font>:<font color="#000000">43</font>:<font color="#000000">25</font> +<font color="#000000">0200</font>
+MODEL    : Back-UPS BX750MI
+STATUS   : ONLINE
+LINEV    : <font color="#000000">230.0</font> Volts
+LOADPCT  : <font color="#000000">4.0</font> Percent
+BCHARGE  : <font color="#000000">100.0</font> Percent
+TIMELEFT : <font color="#000000">65.3</font> Minutes
+MBATTCHG : <font color="#000000">5</font> Percent
+MINTIMEL : <font color="#000000">3</font> Minutes
+MAXTIME  : <font color="#000000">0</font> Seconds
+SENSE    : Medium
+LOTRANS  : <font color="#000000">145.0</font> Volts
+HITRANS  : <font color="#000000">295.0</font> Volts
+ALARMDEL : No alarm
+BATTV    : <font color="#000000">13.6</font> Volts
+LASTXFER : Automatic or explicit self <b><u><font color="#000000">test</font></u></b>
+NUMXFERS : <font color="#000000">0</font>
+TONBATT  : <font color="#000000">0</font> Seconds
+CUMONBATT: <font color="#000000">0</font> Seconds
+XOFFBATT : N/A
+SELFTEST : NG
+STATFLAG : <font color="#000000">0x05000008</font>
+SERIALNO : 9B2414A03599
+BATTDATE : <font color="#000000">2001</font>-<font color="#000000">01</font>-<font color="#000000">01</font>
+NOMINV   : <font color="#000000">230</font> Volts
+NOMBATTV : <font color="#000000">12.0</font> Volts
+NOMPOWER : <font color="#000000">410</font> Watts
+END APC  : <font color="#000000">2025</font>-<font color="#000000">01</font>-<font color="#000000">26</font> <font color="#000000">14</font>:<font c