Author: Shadow8472

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“Beowulf Cluster:” Part 6: OpenWRT Installed

Good Morning from my Robotics Lab! This is Shadow_8472, and today, I’m installing OpenWRT Linux router distribution on a card for a Raspberry Pi 4. Let’s get started!

Background

A while ago, at the beginning of lockdown, I was gifted a few microcomputers I wanted to arrange into a cluster, maybe even turn them into a model supercomputer. I was planning on using OpenWRT, but it wasn’t –and technically still isn’t– available for the Pi 4 outside the use of snapshots. I compromised by configuring a minimal Raspian installation, but I’ve yet to figure out how to program the firewall to disallow computers on its Local Area Network (LAN) from going anywhere online without my say so in addition to keeping them hidden from the Wide Area Network (WAN).

My efforts back then were still possibly the most useful project I’ve done to date: I’ve been using that card as my main Wi-Fi receiver for my workstation. I conjecture it should be just fine with a Pi 4 (1 GB RAM), but since all my more qualified Pi 4’s are busy, my fancy Pi 400 has been serving in that capacity.

Installation

As noted above, OpenWRT for the Pi 4 is only officially available as a snapshot. These builds often lack recommended packages, including any GUI I might want to explore. This is where community builds come in. My research converged on one by wulfy23.

The GitHub’s readme’s took me a while to understand, in part because of all the options. I gathered that there were “factory” builds and “system” builds. Factory builds are for fresh installs, and system builds are for upgrading existing systems. At that time, there were as many as three builds for download, and choosing the right one seemed almost arbitrary.

My first time installing, I totally forgot to check the provided SHA256SUM before unzipping it and dd’ing it to SD card and booting. I landed in a terminal that kept mixing the prompt with other messages. Reaching out to a support thread on the OpenWRT forum, I learned about the web interface, and how to connect to it.

The URL I was given failed every time, even my workstation alone with the router on my switch. I ended up going directly for the IP: 192.168.1.1. I was met with an inadequate dark mode I couldn’t find the settings for. I expect they’re probably there, and I spent a small amount of time looking for them by tossing reasonable sounding URL’s around and hoping for the best, but comparing notes among other tabs in the interface, I think the chances of happening across the specific one I need are slim.

Installation Take Two

I went through the same process another day, and found only a single version for download from the same place. The SHA256SUM checked out, and instead of unzipping it first, I learned about zcat, a little command line utility that can unzip a file to be piped into another command. I piped it directly into dd per an example installation I spotted my first go around installing OpenWRT.

I provided a root password and found a different theme that didn’t force a partial dark mode on me in short order. I found built in tools for ad blocking network wide, settings for managing network interfaces, and most importantly to this project: a fire wall. Alas, the fire wall remains something I have little practical understanding of. I’d like to believe I have a mid-range understanding of what it can do, but my only real hope is copying lines and hoping they do what I want – the last thing one wants in a firewall intended for actual security. No. A custom firewall is at least a week in and of itself.

Takeaway

I really like trying to do two weeks worth of topics in a single week. It usually doesn’t work. Granted: I did have a rusty introduction to both parts of the topic I wished to fuse into one this week. I’m looking forward to remembering zcat in the future.

Final Question

What neat, little tips and tricks have you picked up during a larger project?

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Stabilizing Derpy Chips at Last

Good Morning from my Robotics Lab! This is Shadow_8472, and today, I’m addressing an annoying trio of issues I’ve had with Derpy Chips since I installed PopOS on it. Let’s get started!

The Problems

I have a number for gripes to myself about Derpy. I frequently have to stare at an ugly, gray login screen for to a minute and a half before I can select a user account. Tabs sometimes crash in FireFox, but only while I’m using it. Discord sometimes blinks, and I lose any posts in progress – possibly representing minutes of work.

Additionally, my mother uses a separate account to play Among Us on Derpy, and I have my account set up with a left-handed mouse she can’t use easily. Unfortunately, Derpy tends to crash whenever I try switching users, so I’ve been using a full power cycle. And that means we need another long, featureless login screen before the actual login. Some day, I really want to figure out how to change a login screen. Aside from how long this one takes, I’d much rather use the KDE one over GNOME 3.

The Plan

Of the three issues I’m setting out to address, long login is the most reproducible. Fickle FireFox and Ditzy Discord happen often enough to make Derpy frustrating to use as a daily driver, but sporadically enough to resist debugging on-demand. So I am planning on spending up to the full week on Derpy ready to catch the errors when they happen.

Going off what I have to start with, I’m assuming my FireFox and Discord issues are related. Both use the Internet for their every function, and the glitching tends to happen at times when a packet is logically being received: for FireFox, when a page is either loading or reloading, and Discord when someone is typing or has sent a post. If I had to hazard a guess, I would have to say Lengthy Login is directly caused by my NFS being mounted in /etc/fstab, and I’m not sure if there’s anything to be done about it except working the surrounding issues.

For this week, I an reaching out to the the Engineer Man Discord and a Mattermost community I found for PopOS. I don’t know much about the latter, but I heard the PopOS dev team frequents that forum.

The Research

I started by posting about my issues. Help was super-slow, and I often got buried. I don’t remember any self research making any sense. Anyone helping me in the PopOS support chat seemed obsessed with getting me to address Blank Login first, even though it was the least annoying of my three chosen issues, if only other stuff didn’t bug out on me.

Someone gave me a journalctl command to check my logs, and I did so shortly after a target glitch. It came back with a segfault error of some kind. I added this to my help thread and humored them about disabling my NFS fstab lines.

RAM or Motherboard?

When researching further for myself, I came across a number of topics I didn’t understand. I didn’t make any progress until someone told me to try memtest86+. What a headache! I installed the package, but had to dip into GRUB settings so I could boot into the tool. Even then, it kept crashing whenever I tried to run it with more than one stick of RAM at a time, as in the whole thing froze within 8 seconds save for a blinking + sign as part of the title card.

I was hoping at this point it was just a matter of reseating RAM. Best case: something was in there and just needed to be cleaned off. Worst case: a slot on the motherboard might have gone bad, meaning repair might be one of tedious, expensive, or impossible.

I tried finding the manual of Derpy’s motherboard, but the closest was the one for my personal motherboard, a similar model. Both come with 4 slots of RAM: two blue, two black. I used the first blue slot to make sure each stick of RAM passed one minute of testing, followed by a full pass of testing, which typically took between 20 and 30 minutes. I wasn’t careful with keeping my RAM modules straight, in part because I helped clean my church while leaving a test running.

I identified the fourth stick from a previously tested one I’d mixed it up with by how it lit up the error counter, starting just past one minute in. I tried reseating it several times, with similar results: the same few bits would sometimes fail when either reading of writing. If I had more time, I would have a program note the failing addresses and see if they were the same each pass as they kept adding up.

Further testing on the motherboard involved putting a good stick of RAM into each slot. Three worked, but one of the black slots refused to boot, as did filling the other three slots. I landed with leaving one blue slot empty for a total of 12 out of 16 gigs of RAM.

NFS Automount with Systemd

I still want relatively easy access to the NAS from a cold boot. “Hard mount in fstab has quite a few downsides…” cocopop of the PopOS help thread advised me. Using the right options helps, but ‘autofs’ was preferred historically and systemd now has a feature called automounts. I thought I might as well give the latter a try. cocopop also linked a blog post On-Demand NFS and Samba Connections in Linux with Systemd Automount.

I won’t go into the details here, but I highly recommend the above linked blog. It didn’t make sense at first, but after leaving it for a day, my earlier experiences with fstab translated to this new method within the span of about an hour total. I missed an instruction where I was supposed to enable automounting once configured, but it felt almost trivial.

Results

I haven’t had any problems with Discord or FireFox since setting the defective RAM aside in the anti-static bag it came in. As a bonus, switching users works correctly now as well.

NFS mounting is now much more streamlined with systemd. While I cannot say which method would have been more challenging to learn first, the tutorial I was following made this new method feel way more intuitive, even if file locations were less obvious. I didn’t even need any funny business with escape characters or special codes denoting a space in a file share name.

Takeaway

It really should go without mention that people will only help each other with what they know. I find myself answering rookie questions all the time when I’m after help with a more difficult one. Working side by side this week on a future topic, I had such a hard question, people kept coming in with easier questions, and I ended up asking mine enough times someone commented about the cyclic experience. The same thing kept happening with the easy part of my question about login.

Final Question

Do you ever find yourself asking a multi-part question, only to have everyone helping you with just the easiest parts you’ve almost figured out?

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Virtual Machines: a Preliminary Exploration

Good Morning from my Robotics Lab! This is Shadow_8472, and today, I’m teaching myself a long-overdue skill for Linux: Virtual Machines. Let’s get started!

Overview

Virtual machines are like a computer within a computer; a host operating system allocates some of its resources to a less powerful computer, often with an entirely different operating system. Applications vary from getting a feel for a new Linux distribution before/without installing it on baremetal to giving scammers a sandbox to waste their time destroying without risking your actual system.

Failing other methods with less overhead, virtual machines are a more brute force way to run old or incompatible software on your machine. One personal example from my past was a 16 bit Bible program I liked the interface for. Windows 7 wasn’t happy running it, but there was a special XP mode I could boot into and run my program. I found the solution slow and clunky, and I didn’t use it but twice. Furthermore: the license didn’t extend for Windows 10, so I refused to use it on principle when I downgraded.

Choosing a VM

Wikipedia is a great place for finding software comparisons. Their list of VM’s is quite lengthy, but I wanted a general purpose VM solution I could use anywhere and run anything, as I had an idea I wanted to try on a Windows machine, but my main focus would be running one Linux from another. I was also trying and failing to keep an eye on weather a VM was using a type 1 hypervisor (better performing) or a type 2 hypervisor (more portable/debugable – I think) to run a guest OS.

Looking into individual results, Oracle Virtualbox came out as having a reputation for being easy, even for beginners, though it does lock away some features for a premium version. Free and Open Source KVM (Kernel Virtual Machine) also came up as a better performing, but harsher on the barrier to entry. Further research from LinuxConfig article “Virtualization solutions on Linux systems – KVM and VirtualBox” warned me that KVM may not be as enthusiastic as advertised when it comes to running outside Linux on Linux VM’s, and that I’ll probably want to learn both at some time when I revisit this topic to straighten things out with QEMU and other elements I’ve glossed over while reading about.

Installation: First Attempt

While my goal when starting research was putting a VM on my father’s Mint machine for unrelated –and soon outdated– reasons, I started on my older, but more capable Manjaro machine. I found VMM, a package in a community repository for monitoring VM’s, so I installed it, though poking about only yielded error messages.

It took a while, but it looks like my CPU doesn’t support everything I need for running VM’s. None of my personal computers do. During my initial investigation, I looked up my CPU model on Intel’s site. From what I saw, it supported Intel Virtualization Technology (VT-x), but not Intel Virtualization Technology for Directed I/O (VT-d). One guide only mentioned the former as a requirement, but no package for KVM proper showed up when I searched for it. Furthermore: any commands that look through my CPU’s info properly don’t see the required component.

Takeaway

So, no. I’m not doing a VM today, but when I looked at my father’s Mint box, the newer CPU did support virtualization, and by extension, ButtonMash should too, though their other resources may limit useful applications.

This week’s research has also given me insight as to why XP Mode was so clunky those years ago. I was sending my hardware in directions it wasn’t designed to go. It can still pretend like it’s up to the task, and for old enough applications it doesn’t matter. But hosting a modern OS on top of a modern OS is not for me at present.

Final Question

Have you ever gotten closure to an old project years after laying it to rest?

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Family Photo Chest Part 12: Early Prototype Workflow

Good Morning from my Robotics Lab! This is Shadow_8472, and today, I’m recounting the tale of my first working prototype, and how I ruined it before getting it to actually work. Let’s get started!

Pi4 8GB and Cards

I am now the owner of a Pi4 with 8GB of memory, the highest end Pi available at the present time. When I unboxed it, I put it directly into a case with a fan powered by GPIO pins. Some day, I’ll want to benchmark its cooling against my Pi 4 with the huge heatsink case and passive airflow.

The cards I had on order never came in, and their listing vanished in the meantime. I ended up with some 64GB cards from Gigastone that are supposed to be better on paper, but I’m not in a position to benchmark the Raspberry Pi use case. While these new cards only have one SD adapter between them –I’ve been using SD adapters for labels– they did include a USB adapter. It’s only 2.0, though.

Manjaro ARM

I have not fully settled on what distro to go with for this project. TinyCore is great for starting projects, but I have a hard time finishing it there. For the time being, I’ll be prototyping from my Manjaro ARM card. Whenever I need to reset, I can boot a Pi to Raspberry OS and arrange for a direct dd from my master Manjaro card to the newer, larger card.

Side note: While performing my first wipe, I noticed dd did NOT automatically expand the partition like I thought it did. Once I have things working better, that may be a possible improvement to look at for a new master Manjaro card.

Prototype GIMP Configuration

First order of business was installing GIMP and XSANE plugin for GIMP. They worked first try, but XSANE only recognized a shared network printer all in one with a scanner built in, ignoring the local USB scanner I cannot seem to arrange access permissions for correctly. I think I spent half my time this week on this problem exploring dead ends.

The most important missing piece to the puzzle has been a script called Divide Scanned Images. With it, I can feed it scans containing multiple pictures, and it can separate and crop them automatically with the option to deskew (rotate to vertical) if an appropriate utility is found. Link to blog about script: how-to-batch-separate-crop-multiple-scanned-photos. Linked on that page in a comment by user Jan is a Linux-compatible version of Deskew (I have yet to get it to work).

Eager to test what I did have working, I went ahead with using the scanner on the network. I had someone put some picture stand-ins on; I got two seed packs. To my annoyance, the separation script appears to only work with pictures on file and not freshly scanned in, making it a completely separate process. As mentioned above, Deskew refused to work. I suspect I either didn’t put it in the right place or I was working with a copy compiled for an x86 processor while on an ARM based system, though it could be as simple as shadows from the seed packs.

Struggling With the Scanner

I find SANE to be an ironic acronym: Scanner Access Now Easy. I still don’t have Linux scanners figured out. I know there’s an easy way with security implications I’ve stumbled my way through before. I also have learned that differences between distros make the Ubuntu page I keep getting thrown to for help useless in parts. Whenever I post for help on Discord, someone else comes along with another question and mine gets buried.

Along my journeys, I’ve learned about a scanner group. I tried adding it to my profile, and somehow managed to get what appears to be a fake group. After a long time trying to figure out how to safely remove it so I could add the real one, I managed to remove myself from all my default groups including my ability to use sudo, and I don’t believe a root account is set up on this card. It even said the incident would be reported. Any such black mark never had a chance to be transmitted over the Internet –WiFi was down for USB scanner diagnostics– before I dd‘ed the master copy back over it.

Another attempt had me searching through the local files for answers. sane-find-scanner and anything looking at the USB port directly can see the scanner right away, but scanimage -L to list devices SANE sees comes up with nothing when off the network. I can’t reproduce my exact path on the laptop I’m working from, but I found a tip to check /etc/sane.d/ for appropriate config files. If I understand epson.conf there correctly, my problem is either elsewhere, or I need both a product ID and a device ID, the later of which I still have no idea how to locate.

Revised Workflow Proposition

In the light of GIMP seemingly not wanting to split pictures live in memory, it may be a good idea to offload that task to a more powerful computer that can handle two Pi’s operating scanners and saving to a network share hosted on an SSD before saving the pictures to GoldenOakLibry. Touch up can then happen in-place.

Takeaway

While I’m glad to have gotten a subpar prototype operational, it’s only about 60% of the process demonstrated at once. Still, it was the missing pieces demonstrated, and the toughest spot was exactly where I expected from past experience. This is already Part 12 of this ongoing series, and I want to finish before another 12 parts go by. Any month may be the month, and no matter how down I feel at the end of work on it, I still made a major goal this week.

Final Question

What was the biggest mistake you’ve ever made but still had a minimal effort fix for?

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Space Engineers: Gravity is Stronger Than Thrust

Good Morning from my Robotics Lab! This is Shadow_8472, and today, I’m changing my goalposts and slapping a finished sticker on last week’s project. Let’s get started!

The Design

Where to start now that I’ve “finished” this project? The hull is defined by ship’s systems, but ship’s systems have to fit inside the hull. The whole point of this craft was to make a craft that could bore in its own silhouette without as much overhead, and the simplest way to do that is some take on the cylinder.

In the interest of added visual appeal, I played around with different angles all along the length of my design. The cockpit is as close to a sphere as I can get and still have major flat regions. I added a skinny neck just because, then a larger habitation section with two decks: a multipurpose room and fuel storage/airlock. My cargo hold also houses most of the ship’s batteries, and engineering has a bunch of engines I’m basically lugging around and a tiny secondary cockpit in the very back. Each section listed above — aside from engineering and auxiliary control — is individually pressurized using doors.

When I went to start adding thrusters, I found all my fancy angled hull sections lacked adequate mount points. I adjusted my spreadsheet to find I could boost my effective thruster power by adding nine small thrusters to each big one, at the cost of an extra couple blocks footprint. I sent my new number through my spreadsheet again, and found I’d only need about ten “super thrusters” to hover.

Oversight

I totally forgot about the weight of the ship. In fact, I couldn’t figure it in because of the way the game reported my mass including the ground-based station I was attached to, as well as any ships docked to it. As a result, when I went for my first nose down test, I wasn’t able to back out of my hole, even though it was a third full, tops.

And with the power of extra thrusters comes greater draw on the power grid. I totally neglected to run the numbers before taking off, and found my batteries maxing out while accelerating upwards. I can probably hover under max load, but I’m also looking at the overall battery life. There’s also the fact that I’d like to relocate my base to a nearby mountain top for a bit more light. The air up there is thin enough to where the thrusters I’m using are not as effective.

Game Boundaries

Many games hint at their boundaries before you run into them. They may take the form of an invisible wall marking the edge of a level or a second stack of objects denoting a limited size inventory.

Space engineers has a feature that lists every intractable part of a ship or base your interfacing with. User-defined groups let you manage several parts at once so you can do turn on all the drills or toggle the lights. Maybe all the batteries need to recharge. What this feature lacks is a means to select a range of parts. (Edit in post: Feature does exist, it’s just my right shift key closes the window.) When I found myself with 300+ small engines, I had to click on every last one of them, and it wasn’t fun.

Another lacking feature as I’m finding is the inability to manually move items around. After a marginal amount of research on the official Discord server, someone introduced me to sorter blocks’ unadvertised function of pumping ships’ inventories dry of all matching items.

Takeaway

Game developers will generally have an idea of the scope of the stuff their target audience of players will be doing. Wandering off the intended set of use cases can lead to frustration, but every so often, it can lead to art.

My ship isn’t the easiest thing to look at. It’s covered in way too many engines for its own good, and it still accomplish its mission of hovering while pointed straight down under full load. It’s still more capable than my first ship, which I’m thinking will make for a nice shuttle pod later on.

Final Question

Have you ever set expectations high for a project, only to settle with something that’s still better than you presently need?

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Space Engineers: How to Balance Thrust with Gravity

Good Morning from my Robotics Lab! This is Shadow_8472, and today, I have been working on a ship in Space Engineers. Let’s get started!

Space Engineers is a game where you mine resources on planets, moons, and asteroids to build bases and ships. Over my time playing it so far, I’ve noticed many simplifications, like just how step rough terrain can be before my character slips, or the peculiar arrangement of planetary ore. The physics of moving things around, on the other hand, remains more true to life.

Early Game

For context, I’ve been playing “survival” mode: that is to say I started in the Solar System map on the Earthlike planet. It took me a couple tries before I got a self-sufficient base, but I have successfully made my in-game home in the mountains at a high elevation.

Early on, ore is carried by hand in a backpack. I eventually built a little flying truck and taught myself how to fly by trial and error. Without enough downward thrust when fully loaded, I involuntarily go bumping along the ground, and landing gear explodes, leaving scrap metal behind.

I quickly outgrew my little golf cart, so I built my first ship with an interior and equipped it with mining drills. Each time I rearranged its insides, a little more character became permanent features on the hull. I installed multiple systems I didn’t strictly need, like a Hydrogen tank and engines to generate power from an ice splitter. The trickiest of all was making the whole thing airtight and pumping in Oxygen from a tank.

My finished product was about twice as long as I expected, and quite a bit wider. In practice, I have to make multiple passes at the same area, slowly opening it up until I can reach in and get what I’m after. I’m prone to bumps and nicks, and if I drill too far in, I will catch on something, twist on my axis, and start losing control.

Just as important to an individual ship’s success is the ground station’s work. I did the math once, and found my eight little engines could hardly keep up with the power output of one of my batteries. Left to itself, in theory, it can fly roughly 1 minute for every 5 it spends recharging from an on board Hydrogen supply. If it has to split the ice itself, I could be looking at a quarter of the productivity. A well equipped base can generally top the batteries off in three minutes when I tell them to recharge.

New Ship: Concept

The game has two “grid” sizes for building: large and small. Coorisponding blocks take more components to build on larger grids. Storage blocks have much more volume; the biggest coming not quite to half a million Liters of capacity on a large grid. I want to fill one with a small grid ship. At the same time, I’m remembering when that little shovel of a vehicle I built turned upside down on me because it was overloaded. I want to fly the first time without any accidents due to skipping the math, because this ship will be a lot harder to “just unload.”

How Many Thrusters?

The actual number pulled from in-game is 421,875 L. Small grid large containers are 15,625 L, an 27 (or three cubed) fold increase. I spent some time designing a cargo bay with these numbers, and came up with a repeating design with 7 segments of 4 where I can access each container by hand if need be, leaving me with 28 containers and a cargo capacity of 437,500 L.

My experience to date is only on the Earthlike planet, so that’s where I’ll be designing it to operate. Ores can be really deep in the ground, so I’ll want enough reverse thrust to hover when pointing straight down under full load so I can back out of a hole I’m digging. The densest (and only) density among all the ores is .37 L/kg. Paying close attention to the units, I divided my earlier capacity by the density, coming up with a total cargo weight of 1,182,432.432 kg!

The real Earth has a gravitational accelleration of 9.8 M/s/s. Multiplying the weight of the cargo, I get 11,587,837.838 KgM/s/s. Force from the engines are given in Kilonewtons, but conversion is simple if counterintuitive: the Newton is equivalent to the mess of units already present and the decimal just needs to move over. A little rounding lands at 11,588 kN. The thrusters I’ll be using provide 576 kN. From here, it’s a simple matter of division to find I need a hair over 20 thrusters just to lift the payload.

Ship Layout

For this craft, I started with the cargo hold. I stuffed as many batteries as would fit in the gaps and calculated that I’d need the full output of at least 15 batteries. I already have more than that, though I may want additional units for longer battery life.

Moving forward, I have a habitation section. When building, I like to pretend there’s more going on than is mechanically present, so a living space is in order. The cargo hold was tall enough that I had enough space for a second deck, where I added an airlock for entering and exiting the ship, as well as a few ship’s systems: fuel tank, ice splitter for Oxygen and Hydrogen, Oxygen tank, several large Hydrogen tanks. I was having trouble deciding how long to make the habitation section until I took a cue from the length of the big tanks I installed for future space travel, assuming I don’t make yet another one before I blast off.

The third pressurized section is a long neck leading to the cockpit. I’m following the same general idea for a floor plan as my last ship, and this was where my batteries ended up. In this design though, it’s just there to look cool, but in theory should afford a little more leeway when digging. I’ve also included two conduit lines for moving ore back to the cargo hold in case one side gets damaged.

Up in the front is the “spherical” cockpit with a crazy number of drill heads poking out on both the top and bottom. When I took a break for my write up, I was figuring out windows for it, but they’re being a pane to put in without provision for corner blocks that aren’t just a 2D slice. I’m also looking to have redundant ship’s systems below deck. In the case I come under heavy enemy fire (I’m on peaceful for all I know) and the neck snaps, the surviving part can escape to safety and undergo repairs.

All the way in the back, I’m planning on a redundant command center. In the case I’m backing out of a hole I’ve dug or the more dire scenario discussed above, the ship won’t be without a command seat. If I’m going to have Hydrogen powered generators, here is where I’d stack them. I also need a place to stash a whole lot of gyroscopes for rotation control. The overall ship’s design is practically begging for a set of wings, and I’ve read about a so-called gravity drive I can design and build. I’ll be sure to include some connectors to attach such an apparatus if they don’t double for unloading cargo.

Takeaway

Planning a ship is serious business. I’m far from done –probably another couple full days out– but when I checked the weight from the command chair, the dry mass is lumbering in the direction of my earlier ship’s fully loaded mass of about 300,000 kg. I plugged that figure into my spreadsheet, and it told me to expect to need at least 26 engines for neutral lift capability. I’ll of course want to plug the actual number in when I get there, but such is the nature of iterative design: enough extra engines will call for more batteries, etc.

I still have much to learn, like how I’m going to automate that airlock so I don’t vent Oxygen when I go to space, or how to unload all those cargo containers when I dock with home base.

Special thanks go to my father who was there for reviewing simple Newtonian physics.

Final Question

This week was supposed to be a Raspberry Pi week, but I’m out of SD cards, and the cards on order are lost in the mail. What was the last thing the post misplaced for you?

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Space Engineers: WINE Is Not an Emulator

Good Morning from my Robotics Lab! This is Shadow_8472, and today, I am forcing a Windows game to run on Linux. Let’s get started!

WINE Is Not an Emulator

Gaming on Linux hasn’t always had the best reputation. Software written with one operating system in mind may require the presence of libraries only found in that system, and for the past few decades, that’s meant Microsoft Windows has become the standard for PC gaming.

WINE is a compatibility layer. Their mission is to replace the proprietary Windows libraries with their own open source ones that anyone can freely use. Using WINE, Windows exclusive titles run in “Wine bottles” (or Wine prefixes) that make the correct system calls to either Linux or Mac.

Due to copyright reasons, WINE isn’t allowed to copy-paste any code they look at. Imperfections in execution are an inevitability. Some programs work no questions asked, while others refuse to work all together rated from platinum to garbage.

Steam Proton

I remember seeing someone play Portal 1 on Linux about ten years ago. It one of the earliest titles Steam had running on Linux, but all the walls were blackened like some sort of dark mode. It’s been fixed by now, and Steam will now happily run thousands of titles through Proton, their custom version of WINE. For tech savvy users, they have an option to let any game try to run with no promises provided.

Space Engineers: A Pain to Run

The first time I successfully beat a game into running on Linux with no promises given was Among Us. That game only needed an environment variable or something Proton couldn’t find on its own. Space Engineers, though… it’s something else. ProtonDB lists the game as Silver meaning “[A program] works excellently for normal use, but has some problems for which there are no workarounds” according to WINE’s online database, WINEHQ.

I don’t fully understand what I did in my success. No, Space Engineers will not run easily. My journey started in this community thread on Steam, though the GitHub page they link to is referenced several times over. Just follow the instructions there, and you have a portable black box solution.

But it wasn’t so easy for me. I believe I kept having trouble in creating my WINE prefix. I tried the usual black box rites like rebooting, reinstalling the program, and trying multiple solutions. It wasn’t until I slowed down to find some process hanging in the log that Engineer Man user jeffz instructed me in how to kill the process. Prior to this, I was just using Ctrl+C to kill the process directly in the WINE setup terminal and it would appear to work without the actual game going. I think I managed to rack up a total of 8 to 10 minutes of “play time” in Steam while debugging because not every attempt closed itself.

Followup Work Potential

I pretty much called it good as soon as the game started. Linux discussions kept mentioning “flying grass,” so I was prepared when I saw that, though I have it from a fellow player that there are many bugs even when running it in its native Windows. The only bug I keep running into is an early audio cutoff, usually between the words “Inventory Full.”

My computer is barely fast enough to run Space Engineers smoothly. One of my usual optimizations is ditching the Steam client and running whatever game directly. For a WINE game, though, I’m guessing I’d need to go through the whole process again with another setup, avoiding Proton (I’m using a custom Proton fork by Glorious Eggroll, a recommendation from the ProtonDB page). Unless there’s a DRM requirement where I must use Steam, I’m fine not getting the achievements or other end-user visible hooks. I expect I’ll first try getting Among Us to run from Lutris before tackling Space Engineers.

Takeaway

It is my belief that nothing is impossible to get running on Linux given enough time, talent, and compatible hardware are involved. It is also not unheard of for some games to run better on Linux/WINE than on their native Windows due to the lower overhead from the operating system.

I’ve also noticed a discrepancy where WINEHQ has Space Engineers as low as Bronze or Garbage. Looking at both the age and source of available reports, one needs to not draw conclusions about the runability of a particular piece of software in WINE. ProtonDB had reports near both extremes; most reports are summed up as, “It doesn’t work!” but there are more than a few people who gave detailed specifications on how they got it running. I have a working assembly through a lot of hammering until I found the right spot.

Final Question

If you could run any game on a platform it has no buisness running on, what game would you get running on what system?

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Manjaro: Kernel Error

Good Morning from my Robotics Lab! This is Shadow_8472, and my main tower broke last night, so I’m getting a head start on this week’s post. So today, I’m teaching myself how to fix it. Let’s get started!

The Error

I wish I was writing this week about my experience getting Space Engineers to run in WINE. I had spent my Monday in another game only for it to glitch and lose a bunch of stuff. I needed a break, but not like this:

Warning: /lib/modules/5.10.2-2-MANJARO/modules.devname not found – ignoring
mount: /new_root: unknown filesystem type ‘ext4’.
You are now being dropped into an emergency shell.
sh: can’t access tty; job control turned off
[rootfs ]# _

A lack of keyboard response wasn’t encouraging. Neither was a lack of a response from my usual Linux help places. Still, it’s polite to at least drop the error off for an Internet search, but that is a lot of information to throw around. Any relevant results I got were obscured by my inability to understand them.

As if I weren’t having a bad enough day, I went to try booting to an install disk, thinking it to be for Manjaro. It was for Ubuntu — and it was corrupt. All I saw was what looked like a spaghettified terminal in the pattern glitched spots on the screen were appearing.

Understanding the Error

I tried finding my GRUB disk, but it’s lost. After eliminating bad USB ports as the cause of the corruption, I burned a new Manjaro drive over Ubuntu using my Manjaro ARM card in the Pi 400.

Line-by-line Internet searching for the error didn’t get me much farther than before, but breaking the first line apart was the key because it contains a file path. I booted to my newly reeducated drive and mounted my file system to look around.

/lib/modules/5.10.2-2-MANJARO/modules.devname sounds like a file path, so that was a good place to start. Sure enough, no such file exists, but there is a modules.devname.old file. Looking one directory up, there are a few other similarly named directories in a similar format — the next most recent being 5.9.16-1-MANJARO. It did contain a modules.devname. I considered renaming the old version or copying in the previous one, but I’d have had no idea what I was doing, and there were some slight differences I later found by overlapping transparent terminals — not just side-by-side comparison.

I already knew Manjaro has the ability to install and switch between multiple kernels, but I had no idea where they’re kept or how they work. Using this new information, I looked up the names, and I’m reasonably certain I ended up with a bad kernel on my system.

Fixing the Problem

Now that I had a lead on what to pay attention to in search results, I learned that people are complaining a lot about this and similar kernels released around New Year’s. I would like to try reverting a single kernel and seeing how that works.

One problem: every guide I’m finding appears to assume I’ve already booted to Manjaro and gives either a GUI or command line options for reverting.

In my experience to date, I would have expected I could just go in, flip some strings in config files around and call it a day. It appears I have no such luxury though. That or the kernel is so central to the system that “luxury” is not having to flip 45 such config files, not all of which are meant to be human readable (I have no idea here). Nevertheless, the tool of choice appears to be a command called chroot.

Chroot –as I understand it– is essentially used to CHange ROOT (the directory, not the superuser). It opens a new shell with a root directory of your choosing within reason. It can be used to repair broken operating systems using an external kernel, but there’s a similar concept I am not covering today called chroot jail where users accessing a system from the outside are only shown a subset of the system’s actual root directory.

For this post, I will be using the guide “How to: Chroot into a broken system via live CD/ISO or alternate Linux system” on the turnkeylinux.org to set up a chroot and the command line instructions from “How to Switch Kernels in Manjaro Linux” to revert my kernel.

Side note: a different guide than linked brought up a program called os-prober. I found it in both Manjaro and Debian. When I ran it on my tower, it quickly found my main Manjaro install, but didn’t find my Windows drive I believe to be connected but not mounted. Other methods showed me evidence that it’s still there.

Attempt 1

I didn’t completely follow the set of instructions on how to set up the chroot. I performed them from my root directory ‘/‘. Things started going wrong when my second chosen set of instructions weren’t clear at all about how to manage multiple kernels from the command line.

I started improvising. I tried to launch the GUI version of systemsettings5. Going through the menu pointed straight to the live USB’s kernel, and all its settings no doubt. Going through the command line was fruitless until I had exited out of the chroot and umounted all extra directories, even when I used su shadow8472 to switch to my normal account, a procedure which root could not reproduce after the chroot ended. In short: I did something right, but I’m not done yet.

Attempt 2

This time, my plans required access to the terminal. My plan was to proceed with the same chroot setup, then work my way into a graphical interface hosted with enough elements from my actual tower to work. Any attempts to use a shortcut using Ctrl+Alt+<function keys> only switch to close representations of the true console, but in reality are running on top of that x server I needed to free up. I followed another set of instructions found here, set up the chroot, and it failed.

Third Try

Left with no other options I begin to understand, I moved on with the command line method of actually uninstalling a kernel. I received a stiff warning about how removing the suspect kernel, linux510, breaks a dependency required by linux-latest.

This attempt was interrupted by someone who sounded like he knew what he was talking about suggesting a few things.

The Actual Solution

Changing direction again, I found this Reddit thread that showed me how to expose a GRUB menu for which kernel to boot. From there, I was able to boot a working kernel and get in.

Out of curiosity, I did try to remove the bad kernel from the GUI tool, and it appeared to work until it was still there after a successful report. I was able to bring up the same failure message from the command line in a dialogue box.

Minor Developments

I’ve had tons of issues with my Wi-Fi card, so I turned it off and this week while focused on it, I’ve opened the case, cleaned it, and pulled the card. Maybe it’s software, maybe it’s hardware, but as of this week, I’m using my Pi 400 as a Wi-Fi to Ethernet receiver full time until a suitable replacement can be arranged.

Takeaway

I never realized how far I could get myself sans help on a problem I’ve never seen before. Perhaps I’ve reached a point where my skills are not readily surpassed by those around me. The one recommendation from a person who sounded like he knew what he was talking about turned out to be a dead end (removing the .old extensions from all the kernel modules).

Computer problems can happen to anyone. They’re just easier to learn how to fix without special training on Linux.

Final Question

When was the first time you solved a complex problem you had never encountered before without help?

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Family Photo Chest Part 11: PiCore

Good Morning from my Robotics Lab! This is Shadow_8472, and what a week it’s been! Today, I’m telling you the story of how I’m building up an operating system just to scan photos. This is also a follow up to last week’s topic, where I introduced PiCore as a base. Special thanks to Rich and Juanito of the TinyCore forum who have been answering my questions as I learn about this amazing, little Linux distro. Let’s get started!

Window Manager

I feel like I could do a post or two just on window managers, and I may do so in the future. Long story short, a window manager is responsible for drawing windows within a window server, and not much else.

I now know I used to judge a desktop environment by its window manager without much thought to all the other individual programs going on in the background: a file manager, menus, text and document editors, sometimes even a browser and often a calculator. All of that is bloatware for my purposes. My goal is to have as slim of a system as possible for running GIMP without spending days on end cinching the last megabyte out of the system. After all, I still have to look at it.

Which brings me to my choices in window managers for PiCore. With a smaller tce repository due to being off the main TinyCore branch for X86, I only found a few options. FLWM (Fast Light Window Manager) ships with TinyCore in the main branch. I installed it, and hated all the stuff on the left side. I suppose someone must like it, and I can admit it takes up less vertical space, but I do need at least a few familiar points of reference.

I started researching window managers, but only when I searched tce for keywords: ‘window manager’ did I realize just how short my list was. Least of which was a package that looks like it only multiplexes terminals. One of the admins helping me pointed out FLWM_Topside, but I’m not really a fan of jumping cursors, and I had already selected JWM (Joe’s Window Manager).

I found JWM simplistic and appealing. I had already used it in the past as part of the MATE desktop environment, like what I’m using now. The base version is configured by a text file, which I modified by hand to display a panel at the bottom as opposed to the top. There isn’t even support for calculating that automatically!

I was also sure to remove FLWM packages from tce/optional. There are other spots where it’s left hooks for proper execution, and I’ll weed those out when I see them.

NFS Auto-Mount

Network File System: I’m getting the basics, only for TinyCore, my usual method of mounting shares gets flushed out on reboot. But I can work with the system I have. I can’t give the TinyCore people enough credit: they produced a shell script I could customize and told me how to install it.

Color Depth

Just a note, really: Color depth is a thing. The scanners I’m working with each use 16 bits to say how much of each primary color is present in a pixel. I was warned by user barefootliam on the Gimp Discord server that a XSANE plugin may only use 8 bits. I don’t know for sure at this time, but it’s worth noting.

Amusing Errors

Along the way, the system broke — a number of times even. Early on, I found how to hold Ctrl+C to close xorg as it started and to drop to the command line. Sometimes it was root, other times it was the default user, tc. Now that root has a password, it won’t let me pull that one, thankfully.

Another time, I was changing the default GIMP icons from plain white to color. It crashed JWM. I tried several times, and the result was always the same: All the window decorations around the outside were gone, and I was left with GIMP selected, unable to switch to the terminal so I could save the changes with filetool.sh -b as you do when using TinyCore. I found the sleep command and set a delay to restart JWM using sleep 15s && jwm. At first, I was adding a restart command to jwm, but without JWM running, I was left with a dud command and a brick to forcefully reboot.

Toward the end of this development cycle, I was debugging JWM and moved the config files to a separate directory and restarted the program. Yikes! Turns out it came from the tce repository with a theme of its own. Rebooting once again restored the theme to default, but didn’t solve the empty config file issue.

Future Plans

A computer system is hardly ever a static setup. When I have another SD card, I will want to look into a clean build on the aarch64 version of PiCore. Turns out I’m in the 32 bit version. My dream though is to build it on the 8 GB Pi 4 once I know what I want here.

I may not end up using a Pi at all if it just can’t keep up with my old laptop on its scanner.

Takeaway

TinyCore is a fun operating system. It may be a bit limited due to low popularity, but the community I’ve now contacted gets back pretty quickly. Just know that connections to their site are unencrypted, so if you go there, USE A UNIQUE PASSWORD! It’s just good practice anyway. Here’s a link here to the help thread I’ve been lurking in.

Final Question

What kind of long duration projects have you completed?

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A Collection of Raspberry Pi Projects: Volume 3: PiCore

Good Morning from my Robotics Lab! This is Shadow_8472, and today, I am finishing off the year with another entry into my Raspberry Pi operating system collection. Let’s get started!

I have a number of Pi projects going around now, and not enough Pi’s equipment for everything. My Pi 4 is mainly serving as the family’s entertainment system (I happened to find a Steam Controller driver for it), and my Pi 400 –which I originally intended for that job– is running my Raspian reverse Wi-Fi router card because it’s not supported yet by LibreELEC outside beta releases. I’m tossing these microSD cards around like playthings, and my family has expressed mild concern.

But today, I am taking notes as I build a side project to help with my Photo Trunk project. I have no idea if it’s going to work well, but I’m hoping! Worst case is I learn a few things and move to something more appropriate.

PiCore Installation

I’ve covered Tiny/Micro Core Linux before. I know it’s very much a build-your-own experience type of distro without being totally unapproachable for beginners intent on learning. I am installing it using BlinkiePie (Pi 3B+) with the intention of moving it to a Pi 4 unit later.

The two documents on the download page, IMPORTANT and README, explain how to install the operating system to an SD card and expand the second partition. I followed along more or less blindly.

At one point, fdisk is opened, and I was instructed to “write down the starting and ending sectors of the second partition.” [source] When I listed them, fdisk reported StartCHS, EndCHS, StartLBA, and EndLBA. I looked, but I wasn’t able to find any other examples of fdisk reporting in this way. I only learned about “Cylinder Head Sector” and “Logical Block Addressing” by separating the acronyms. I proceeded to make a new partition, and fdisk was nice enough to mention the largest size I could go.

Construction Pains

I was expecting to start with something resembling the larger “Tiny” Core variant with a desktop environment, but PiCore only has a “Micro” Core image available. GIMP is very much a textbook GUI program, but the tce package manager was more than happy to install it and I estimate fifty dependencies.

I browsed over to the TinyCore forums, and was actually able to activate my account. The connection still isn’t secure, so don’t go using any personal standardized passwords. 50-99 alphanumeric characters with symbols say that’s not an attack vector against me though.

As I was getting ready to look for help in the dedicated Raspberry Pi section, I noticed a thread here where someone was looking to install a desktop. I went ahead and installed xorg, a name I know has something to do with Linux GUI’s, but like the original poster in the thread, I found myself unable to do anything after booting to a simple black screen.

Further experimentation discovered that by holding CTRL+C during startup, I could interrupt xorg from trapping me away from the command line. The results were a bit unpredictable, though. The first time, I somehow ended up as root. Other times, I found myself as tc, the default username, and other times, no login transpired.

I installed the remaining recommended packages, but neglected the window manager. Results were interesting. There was a dock at the bottom of the screen I could interact with, but no visible pointer. I toyed with the setup before rebooting again. GIMP was no trouble to get running with a window manager on board.

Takeaway

In many ways, MicroCore feels like it’s a model operating system. All the parts are exposed but there aren’t so many the mind can’t grasp the overall system. Additional work will need to be done if I want things like automatic connection to GoldenOakLibry or even Wi-Fi for that matter. I still have much to learn.

Final Question

I don’t like the window manager I found. Which one might you recommend?

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