GTALUG Q&A Topics for October 2020

1.1 AGM: Chris’ Financial Report

1.2 AGM Candidates for Board

  • Note: 2 slots for 2 years + 1 slot for 1 year
  • Two incumbents finishing terms:
    • Chris Browne
    • Alex Volkov
  • Also, Stewart Russell has “thrown his hat in the ring”
  • Chris thought that he had email from another would-be candidate, but couldn’t find the email 🙁

1.2.1 Candidates Found:

  • Alex Volkov
  • Chris Browne
  • Stewart Russell

There being 3 slots, and 3 candidates, no vote turns out to be necessary for this.

1.3 PostgreSQL

1.4 Pi Stuff

  • Review of Gempro Pi4 Enclosure It’s made out of a whole lot of aluminium, so the whole case is a giant heatsink, and is apparently interestingly effective.
  • US vendors (Amazon, Newegg) carry it for about $30 USD

1.5 NVFS – Non Volatile Filesystem

nvfs Internals NOVA filesystem NOVA (NVSL) on GitHub

  • No particular discussion fell from this…

1.6 Game of Trees

OpenBSD Game of Trees

  • Uses Git repositories to store versioned data
  • Can use Git to perform functionality not (yet) in Got
  • Intended to be simpler than Git to fit with OpenBSD’s desire to have auditable components
  • Note that FreeBSD is moving from Subversion to Git, and has added Got to their set of packages

1.7 Apple Swift increasingly open source

Swift System is an interface for system calls and low level currency types, now adding Linux support. This means that accesses can have type safety, unlike C interfaces

Swift Playgrounds
An introduction to programming intended for children to teach about iteration and such

1.8 Hello Darling

darlinghq.org, darling @ Github Darling is a translation layer that lets you run macOS software on Linux. At present, it won’t quite so much run GUI applications, though… It’s thus not so much a way to run Photoshop on Linux, and more like a way of running server-ish apps. Maybe it’s a place to host the Swift apps?

1.9 Word Lists

SCOWL – wordlist.aspell.net

  • SCOWL (Spell Checker Oriented Word Lists) might be useful to “spice up” your /usr/share/dict word lists.
  • You can construct your own word lists, based on parameters:
    SCOWL Size
    Indicates the portion of the language covered. The balancing act is interesting; make the dictionary larger, and risk false-negatives, that is, typos being mistaken for extremely uncommon words.
    Dialect Choices
    USian, Canadian, 2 British variants, Aussie
    (no term)
    Spelling variant inclusions
    (no term)
    Handling of diacritics
    (no term)
    Special lists
    • Hacker words
    • Roman numerals
  • Lots of vigorous opinions!

1.10 A fun technical interview

Rewriting the Technical Interview

  • I find it really fun that the writer designed, in-interview, a compiler specifically to parse (and rewrite) a (somewhat awful) program that was pulled off of (I assume) StackOverflow.
  • Note that it’s from a series; each focuses on taking a different, um, “abuse” of programming techniques taking things well beyond any expected limits
    • Reversing the technical interview
    • Hexing the technical interview
    • Typing the technical interview
    • Rewriting the technical interview
  • No particular discussion fell from this…

1.11 Interactive Fiction Competition

ifcomp.org – An annual celebration of new, text-driven digital games and stories from independent creators. In its 26th year!

  • No particular discussion fell from this…

1.12 Object Storage Protocol: POSIX’s death imminent?

New Object Storage Protocol Could Mean the End for POSIX

  • Object storage now has an mmap function mmap_obj() similar to POSIX. That means the processing and scalability limitations of POSIX become the new bottleneck.
  • Of course, perhaps this is tilting at a windmill…
  • No particular discussion fell from this…

1.13 OnlyOffice

  • multiplatform distributed “office software”
  • AGPL licensed
  • No particular discussion fell from this…

1.14 Snek

  • https://github.com/keith-packard/snek
  • By Keith Packard of X11 fame
  • Microscopic Python-like language
  • Can run on tiny, tiny hardware
  • Apparently Lego is adopting it
  • Is this a pure interpreter? Or does it push bytecode or machine code to the runtime environment? see also: https://circuitpython.org/
    • Looks like it pushes the textual code to the runtime environment

1.15 ICANN

GTALUG September 8, 2020 Meeting Notes

1 GTALUG Q&A Suggested topics for September

1.1 AGM Preparations

Hear ye! Hear ye! This is a Call for Candidates for the GTALUG Board.

October 13th is GTALUG’s Annual General Meeting, our tiny piece of “political pageantry.”

There are two seats opening, for 2 year terms (2020-2022).

Please consider running for the board, and keep in mind the following.

There are two formal qualifications that candidates need to satisfy:

  • Must be a GTALUG member in good standing
  • Must not have any undischarged bankruptcy

It is also important to be able to be available most months for Board/Operations meetings where we plan GTALUG meetings and activities. These meetings normally take place on the Monday evening following the regular Tuesday meeting. These days, this takes place on-line, using Jitsi.

This is not an extraordinarily huge burden, but it does mean that there are 48 meetings (counting both “second Tuesday” and “the following Monday”) where we hope to see you, and we hope to see you most of the time.

Board members are involved in and support the following activities.

  • Finding speakers for our monthly presentations
  • Operating our internet infrastructure (website and mailing lists)
  • Organizing and running our annual Linux in the Park picnic (in less pandemic-stricken times)
  • Our involvement as a member organization of ICANN

If you are interested, we’d appreciate it very much if you can submit your intention to run to the email address: board at gtalug.org

The incumbents whose previous terms are expiring are:

  • Chris Browne
  • Alex Volkov

Potential Candidates are welcome to announce their intention all the way up to the day of the AGM itself.

1.2 GTALUG Membership In These COVID-19 Times

In most years, membership has been handled via comparatively informal in-person processes, and those that wish to support GTALUG via membership would (broadly) follow the following steps:

  • Grab a membership form (that Chris passed out)
  • Try to pass Chris a $20 bill, whereupon Chris would say “give it to me along with the filled-in form”
  • Fill in the form, and hand it to Chris along with payment
  • Chris returns a few minutes later with a membership card

As GTALUG is meeting virtually, these days, this process cannot occur as described.

For those wishing to support GTALUG via membership, two routes are suggested:

The Cheque is In The Mail
Send a payment via Canada Post.
Interac eTransfer
Send funds from your bank to ours

To ensure that membership has been addressed for voting at the 2020 AGM on October 13th, it is imperative to handle this earlier than that, as mail can take several days for delivery. Alas, either way, this imposes more bureaucracy and some more cost than we have been accustomed to.

Payment via check using Canada Post

In this case, please send a cheque, made out to “GTALUG”, in the amount of $20, along with the identification information indicated below, and please send to the following address:

GTALUG 914-10 Carabob Court Toronto, ON M1T 3N5

Interac eTransfer
In this case, three pieces of information are critical, and must be shared both with your bank as well as with GTALUG.
Recipient
The recipient email address is membership@gtalug.org
Security Question
The content of this is not too important; “Random Value” or “Sooper Sekrut Data” are fine values.
Security Answer
It is suggested that a random value be used. For instance, 215db45eb7f54e1e5907de3b50ac50ee is a value I got from passing 1K of data from /dev/random through md5sum, and that is a decent mechanism to get a relatively unguessable password. (Of course, since many people have seen that specific value, 215db45eb7f54e1e5907de3b50ac50ee, it would not be a good choice.) This security answer also needs to be emailed to the membership@gtalug.org address in order for us to receive the payment.
Common information
Whichever of the above mechanisms is used for payment, please email the following membership information to membership@gtalug.org. Note that by longstanding policy, we do not pass your information on to outside organizations.
Name
Your preferred name
Email
Your preferred email address (if using Interac eTransfer, it’s best to use the same address, so we know which email address to associate each security answer with)
Address
If you are comfortable providing such
Security Answer
If eTransfer is used, we need the Security Answer in order to actually receive funds

1.2.1 Generating a random value, the Linux way

Here is a script that repeatedly takes 1K of random data from /dev/random, and turns it into an md5 checksum to ensure that the value is human readable and not too long.

for i in 1 2 3 4 5; do dd if=/dev/random bs=1k count=2 status=none | md5sum; done
215db45eb7f54e1e5907de3b50ac50ee  -
4f8f0e3a2944c857ebc3a7a776659134  -
1a52010a29ef3b2446d532ba389f65cb  -
84e6b072e2661fc88b3a7b1ed1ce5873  -
ef3f10a8b634760691e2ae53a0952707  -

1.3 Debconf 2020 was last week

  • anyone make it to parts of that?
  • DebConf 2020 Talks
  • 1.4 Mozilla let some people go 🙁

  • anyone know the impact?
  • appeared to include the folk that had been redoing the browser in Rust (Servo)
  • risk of there being less diversity in the web browser marketplace
  • 1.5 Sharpening your tools: Editors

    Vim – Sharpening the Axe

    This talk/presentation speaks about how it is important to update your editor configuration on an ongoing basis, due to several things:

    • Make the editor serve you better by supporting your individual needs
    • Learn more features, over time, which feeds into the above…
    • Editor functionality is enhanced over time, and making use of those enhancements requires new configuration
    • What tools do you NEED to sharpen?
    • What new tools do you need to create from scratch?

    1.6 Upcoming Conferences

    VimConf 2020
    Apparently was to be held in Japan, but cancelled, for the obvious reasons
    EmacsConf 2020
    Being held November 28/29, on-line
    • Call for Proposals is active now, until September 30

    1.7 Everything rewritten in Rust

    Shell Commands Redone in Rust

    bat
    like cat
    exa
    like ls
    fd
    like find
    procs
    like ps
    sd
    like sed
    dust
    like du
    starship
    custom shell prompt
    ripgrep
    like grep
    tokei
    calculates statistics about a directory full of code
    hyperfine
    benchmarking wrapper
    ytop
    like top
    teeldir
    like tldr, displaying simplified man pages
    bandwhich
    displays network utilization
    grex
    generates a regex that matches test cases
    rmesg
    like dmesg
    zoxide
    autojumper, to replace cd
    nushell
    a shell with pipeline editing ala awk/SQL

    1.8 SSH Honeypot Credentials Analysis

    Lessons Learned from SSH Credential Honeypots

    1.8.1 Interesting passwords

    baikal
    a lake in Siberia
    prueba
    Spanish for test
    caonima
    a Mandarin profanity written in Pinyin
    meiyoumima
    Mandarin for “no password”
    woaini
    Mandarin for “I love you”
    poiuyt
    The name for an optical illusion also known as the “devil’s tuning fork” (A prank from Mad Magazine!) Edit: multiple redditors pointed out this is the beginning of the top row of the keyboard from right to left.

    1.9 Just pretty weird…

    Remember Mach? And VMS?
    I’ll bet you don’t remember that someone implemented a VMS multiserver atop Mach…
    (no term)
    BLISS from CMU…
    (no term)
    Microsoft starting to play games with GitHub

    1.10 Modern Linux desktop layers and performance

    • X11 or Wayland
    • DE; Gnome/KDE/XFCE
    • GTK / QT
    • Firefox / Chrome CODECs, DRM
    • can Gnome applications run under XFCE (with what limitations)
    • why is XFCE faster than GNOME / KDE (compositors using 3d operations?)
    • what CODECS should one install? Are they authorized?
    • how is it that Widevine can work on Linux?
    • interesting ArchLinux notes on Firefox

    2 Calls for proposals for LibrePlanet

    3 CAD software

    • Are there any good open-source tools to edit STEP files(CAD)?
    • FreeCAD? Rather complex…
    • GCAD-3D

    3.1 Anything interesting ongoing with RISC-V

    • Hugh had a recent conference
    • RISC-V is a design for an instruction set that is free to use
    • Many implementations ongoing, many “very free”
    • Aspires to a similar place in the “design space” as ARM, which has
      • Some cheap, nonsophisticated designs
      • Or expensive, sophisticated designs
      • Apple’s newest SOC is their own implementation of ARM instruction set
    • RISC-V has a “gold rush” of organizations rushing to stake out claims
      • Open source implementations of RISC-V are often toys, or academic projects
      • Some companies designing performant RISC-V chips
      • Western Digital is now deploying RISC-V chips embedded in their disk drives
      • Some of the implementations are basically like a 32 bit Arduino implementation
      • Lots of “sort of open source” implementations
      • Might be popular with Huawei because they can’t get at next versions of ARM due to US bans
      • RIOS (RISC International Open Source) moved out of the US to Switzerland to avoid US law
        • Collaboration between Shenzen university and Berkeley
        • initial plans involve a RPi-like design that is to be open source, provided by AliBaba
        • Some parts open source (CPU) others possibly not as much (USB)
        • Needed to add some custom instructions to accelerate their work load
        • Interesting to get something including MMU, perhaps even GPU

    GTALUG August 11th Notes

    Table of Contents

    1.1 Keybase Alternatives

    • Keybase has offered secured accesses to various sorts of data
      Key directory
      Associates social media identities to encryption keys
      • Twitter
      • Github
      • Reddit
      • Hacker News
      • Mastodon
      • Cryptocurrency wallet addresses
        • Bitcoin
        • Zcash
        • Stellar
      (no term)
      End-to-end encrypted chat
      • Quite a lot of us are using Telegram and Signal
      • Essentially amounts to encrypted chat; many parts are open source
      • Encrypted instant messaging and VOIP
        • Client is free software
        • Server is proprietary
      KBFS
      Encrypted filesystem
      • Public files
      • Private files
      • An end-to-end encrypted, peer-to-peer file storage, sharing and communication network
      • We used this for GTALUG a bit for exchanging server data across the executive
      Teams
      Encrypted chat, fileshare
      • For just key validation keyoxide, I’ve heard of it, have no experience yet. keyoxide.org
        • decentralized
        • MIT licensed

    1.1.1 Element

    1.1.2 The moderation problem

    1.2 Neat Monitoring observation

    Should put obvious information into monitoring alerts

    • The temperature alert that points to calling building managers should include contact information
    • When you create an alert, think through what those reading the alert will immediately want or need, and note that what is obvious today, when we’re reacting to the outage that caused us to set up the alert, may be less obvious in 18 months when a new sysadmin looks at it
    • Put those needed/wanted things in the alert, possibly as a link, tho in case your Wiki might go down, probably the phone number ought to actually be in the alert.
    • Make sure there aren’t any credentials in the alert text!
    • Motion-sensitive camera that gets activated when the sun comes up through the trees in the morning
      • what is the difference between burglars and squirrels and sunrise
      • hurray, flying burglars!
    • Useful to have some alerts suppress other ones

    1.3 Have you changed your ssh keys lately?

    SSH Keytypes Usage

    • There are new algorithms that are theoretically more secure than the old ones
    • Are you using your keys for too many services?
    • ssh config lets you specify per-host keys

    1.4 Have you labelled the disk drives in your desktop?

    Label Your Desktop Drives

    • Using a Dymo label maker or similar
    • Brother apparently makes much nicer label printers
    • Scott Sullivan was literally just preparing a label to attach to a recently scrubbed hard drive
      • need to know the serial number from the drive in a cheap RAID array
    • Howard pulled out a typewriter!
    • Drew generates a 4 digit number for each drive and keeps those as the “key”, sharpie is good enough
      • For personal use, this supports 9999 drives, which is enough; perhaps 3 digits (999) would suffice
      • For organizational use, a bigger serial number would be needful
    • Business cards attached with packing tape

    1.5 Raspberry Pi 4

    • There have been ongoing discussions about building a “Pi Desktop”
    • Evan suggested a notably better case (but that Scott had already posted!) but that was somewhat expensive
    • Budget was not especially clear
    • Initially, Pi4 was running extremely hot, but with modern software releases, way better/cooler

    1.6 IPv6 versus IPv4

    Interesting essay showing some of the inherent conflicts

    • Once you configure prefixes on the router, often Linux, Windows, MacOS often “just work” these days
    • Mozilla Addon ipvfoo-pmarks shows off IPv6 usage

    1.7 Latest grep reimplementation

    ugrep
    written in C++ 2011
    • can search inside compressed archives (numerous sorts, .jar, .zip, tar, .cpio, and compression such as .gz, .bzip2, .xz, …)
    • can search inside documents (.pdf, .xls, .docx, …)
    (no term)
    sift, written in go, parallelizing: https://sift-tool.org/
    (no term)
    ack, written in Perl, extended to do version control, graphics metadata https://metacpan.org/pod/distribution/ack/ack
    (no term)
    rg, written in Rust
    (no term)
    Full text search on Gnome desktop, locate was an olden days standard service
    • `mlocate` is a more user-friendly version of locate
    (no term)
    Tracker seems neat
    (no term)
    Find is still pretty useful
    (no term)
    FSELECT is a Rust-based command line tool that’s loosely find with SQL-like syntax

    1.8 Pinephone now available

    1.9 LibreOffice 7.0 released recently

    1.10 Perl 7 almost out

    1.11 MathML?

    I am using Octave and LaTeX to do calculations and write reports. Conceivably, I could output to HTML instead, but MathML does not seem to work on all browsers. Is this interesting to anyone?

    GTALUG Q&A July 14th, 2020

    1 Notes from GTALUG Meeting 2020-07-14

    1.1 Have you checked NTP recently? (Chris)

    • Upgrading DDWRT on a DIR-632 showed off that ntp config had been broken for years
    • Also router was pointing to DNS on a host that had been gone for years 🙂
    • I always used to use echo dmpeers | ntpdc to check synchronization
    • That apparently stopped working, probably years ago
    • The modern thing is the following:
    root@karush:/var/log# ntpq -p
          
         remote           refid      st t when poll reach   delay   offset  jitter
    ==============================================================================
     0.debian.pool.n .POOL.          16 p    -   64    0    0.000   +0.000   0.000
     1.debian.pool.n .POOL.          16 p    -   64    0    0.000   +0.000   0.000
     2.debian.pool.n .POOL.          16 p    -   64    0    0.000   +0.000   0.000
     3.debian.pool.n .POOL.          16 p    -   64    0    0.000   +0.000   0.000
     LOCAL(1)        .LOCL.          10 l  537   64    0    0.000   +0.000   0.000
     nash.int.linuxd 44.190.6.254     3 s   25   64    1    0.464  -19.446   0.000
     bellman.int.lin .XFAC.          16 s    -  128    0    0.000   +0.000   0.000
     time2.facebook. .FB...           1 u  119   64    2  271.399  +102.36   0.000
     192.168.0.63    .XFAC.          16 s    -  128    0    0.000   +0.000   0.000
     hpaq.int.linuxd 45.79.13.206     3 s   54   64    1    0.283   -4.946   0.000
     karush.int.linu .XFAC.          16 s    -  128    0    0.000   +0.000   0.000
    *ntp1.torix.ca   .PTP0.           1 u   19 1024    3   48.489   -5.496  79.828
    +68-69-221-61.nb .ROSS.           1 u   23 1024    3  138.782  +25.387  39.417
    +ntp2.wiktel.com .GPS.            1 u   23 1024    3   72.396   -7.548  79.119
    +montreal.ca.log 172.105.103.85   3 u   27 1024    3  112.404  +22.622  40.738
    +208.67.72.50    128.227.205.3    2 u   24 1024    3  101.382   -9.729  95.870
    +clock.sjc.he.ne .CDMA.           1 u   37 1024    3  106.625  -11.264  97.836
    +ntp16.doctor.co 50.205.244.28    2 u   42 1024    3  133.717  +24.106  39.239
    +time.cloudflare 10.14.8.68       3 u   42 1024    3  111.500  +22.664  38.322
    +198.255.68.106  192.168.1.193    2 u   40 1024    3  117.507  -13.853  95.332
    +strongbad.voice 200.98.196.212   2 u   43 1024    3   60.177   -8.618  78.205
    

    1.1.1 (Bob B) Can anybody explain what all that stuff in the ntpq output means?

    • Some answers can come from “official NTP”…
    • lol RTFM!
    • still, good question, I’m happy to read thru it……. no, you are correct….. that’s a great page!
    • Chris did a “broad strokes” explanation of much of what was in there, which he hopes gives enough background that the deep detail of the “official” explanations aren’t as overwhelming.

    Scott S pointed out – Info on REFID

    1.2 (Bob B) What are people using for centralized authentication at home labs? Really don’t want AD.

    1.3 (Scott S): Opensource Physical Resource management

    • Room and Equipment bookings.
    • Integrations, MQTT, API
    • Hacklab needs this sort of thing from two perspectives:
      • With COVID-19 still around, they’d like to be able to trace where people have been and where and what physical resources they have touched
      • There is a need to arrange fair bookings for resources like 3D printers, as they now have some fairly reliable ones that will attract a lot of usage requests
    • No real answers came up in discussion
    • Later link added: List of Open Sourced Software for Resource Scheduling and Booking

    1.4 Question: (cbbrowne) Has anyone been making use of the new-ish packaging systems?

    AppImage
    a packaging format
    Snappy
    Canonical sponsored central app repo
    Flatpak
    central app repo, but individuals may host too

    In principle, these are supposed to make it easier to deploy applications where you want faster evolution than distributions offer. (E.g. – [https://wiki.debian.org/DebianReleases][Debian takes For-Ever to get new versions out…]])

    • Nobody seemed to be too much a fan of this
    • It was suggested that this concept was popular for developers that want to do their own thing, and that hate the idea of distribution makers renaming any of their stuff. This suggests a lack of appreciation for policy, which is why distribution makers do that sort of renaming…

    1.5 Question: (cbbrowne) Anyone using mesh networks yet? (802.11s)

    • now supported (if your hardware does) on OpenWRT
    • bridges networks together to give better network coverage by having devices talk to all the routers around them
    • Easy? Hard? Security pains-in-the-neck?
    • new router standards are coming out – 802.11ax aka WiFi6 so probably a good idea to wait

    1.6 Question: (cbbrowne) anyone been playing with the modern terminal fonts that are emerging?

    • Inconsolata
    • Mononoki
    • Ubunto Mono
    • There are barrels more of these
    • Some amount of trying to be kewl
    • some amount of trying to be readable+distinguishable (0!=O) even in small font sizes

    1.7 Security Question of the Month: Have you updated your router firmware lately?

    • OpenWRT just had a new major version (v19) released in May
    • DDWRT has per-device upgrades; how their versioning system is not especially clear
      • Did an upgrade from “v24” (from 2013) to “v3.0” (2019), that’s not overly clear!
      • DDWRT has some pretty proprietary stuff; means they can support Broadcom
    • OpenWRT is a bit better known than pfSense
      • OpenWRT pretty attractive for a place like Hacklab
      • can run Ansible against it!
      • Specialized Ansible for OpenWRT
      • UCI commands (can be seen in the LUCI Web UI) generate configuration; you could use these commands yourself
      • Also consider using Ansible commands + Ansible templates
    • Probably worth looking into pfSense on slightly better hardware
    • Ubiquity edge routers are good for non-wifi contexts

    1.7.1 Recommended OpenWRT Routers

    1.8 CHUWI LarkBox

    GTALUG EtherPad for Meeting of June 9, 2020

    1 GTALUG 2020-06-09

    1.1 Hugh on UEFI for ARM

    Is the raspberry pi sufficiently open so to allow a single distro to be adaptable for multiple different SBCs?

    • Raspbian is often used (forked to “armbian” for other systems)
    • Different devices often need what is termed a “device tree” that is unique to a board or family of related boards
    • Annoying thing about ARM is that many have GPUs, and unfortunately most of the GPUs have issues with NDAs so that it is troublesome to share low level code

    What are your thoughts on using Anaconda in Ubuntu or other Linux distro vs installing all Python packages and using Python virtual environments instead? I’m coming from Windows, so Anaconda was a straight answer, but now that I’m becoming a Linux user, is not that clear that I should use Anaconda, and could better learn to use the Python venv. Just wanted to get some thoughts.

    • pyenv
    • Should we use distribution-managed packages? Or build a virtual environment to pull fresh code?
    • These days, scripting languages have their own dependency systems which makes life difficult for distribution makers.
    • Awesome Alex, thanks for your thorough explanation, I’ll certainly look into pyenv…. my name is Nestor Sanchez btw…

    1.3 Python II – the Sunsetting of version2

    Note that Python 2 is officially sunsetted… https://www.python.org/doc/sunset-python-2/

    Some old Python code still lurks in distributions.

    1.4 Powershell

    Has anyone been playing with Powershell? What sorts of differences are there between that and our favorites?

    • It grew up with Windows so has lots of Windows bits
    • It operates on streams other than Unix “bags of bytes” which can be very different

    1.5 WFH Learning

    • I changed my commute time for walk/run around the neighbourhood time. To keep some routine.
    • Some tendency for longer days because we aren’t consuming any time on commute but maintain broadly similar hours
    • Daily “stand-up” meetings (common in SCRUM methodology) are useful to add a little bit of personal discipline
    • Audio bandwidth limitations are an issue
    • Microphones on laptops that are picking up fans and refrigerators are common problems
    • Microphones intended as speaking headsets provide improvement

    1.6 ROCm

    Any experience among this group with using ROCm for high performance computing?

    1.7 systemd, 10 years later: a historical and technical retrospective

    systemd, 10 years later: a historical and technical retrospective

    • everything needs to be decrudded once in a while

    1.8 JITSI results

    • mixture of opinions, for sure
    • a couple of people fell off the meeting, so not impressed
    • several reporting that sound is quite good
    • user interface is quite comparable to Google Meet and Zoom
    • Can use custom backgrounds similar to what are commonly done on Zoom

    1.8.1 Custom backgrounds for videoconferencing

    Get a green board to go behind, and then compile a virtual camera Using OBS Studio for Google Hangouts/Meet

    • implements a virtual camera that allows putting arbitrary backgrounds behind you
    • GitHub: CatxFish/obs-v4l2sink
    • I made a green screen for chroma key out of 4 pieces of green bristol board from Dollarama.
    • This can work with Jitsi, Zoom, Google Meet

    1.9 Upcoming events

    GTALUG Etherpad for May 13, 2020

    1 Notes from GTALUG Meeting 2020-05-13

    1.1 Running kvm (kernel virtual machine) on Raspberry Pi

    • Yes, it is possible
    • Raspberry PI 3 and above have HW support in the chip and bootloader
    • Possible to run it with docker
    • KVM can run x86 code or ARM code on any machine
    • The problem with ARM – No standard BIOS, an implementations with UEFI and device tree. Not trivial.
    • A version of kubernetes k3s (a simplified version) Runs on Raspberry Pi (containerization not kvm)
    • not a lot of documentation on how to run KVM for raspberry pi
    • Raspberry PI is typically 32-bit vs all of the ‘serious’ containerization projects prefer 64-bit ARM platforms
    • k3s (a sorta cheap Kubernetes) on RPi

    1.2 Has anyone tried POP!OS?

    • POP!OS?
    • An Ubuntu derivative
    • Reviews say this is the most beautiful thing since Elementary OS
    • Produced by system76
    • Really nice UI from the experiences
    • GPU drivers seem to be supported on more stable distributions (RHEL & CentOS) and not Fedora (specifically GPU computing from AMD or Nvidia)
    • Fedora 31 hung on used Dell XPS with NVIDIA graphics
      • ubuntu just works (proprietary drivers)
      • fedora 32 has nouveau
    • POP!OS seems to have sensible defaults
    • /r/popos
    • this is where System76 announced POP!OS, in 2017, when Ubuntu stopped working on Unity

    1.3 Video conferencing for teaching a-la software carpentry

    • (group breakouts & shared screens in small group only)
    • What is software-carpentry.org
    • Teamviewer available for linux but proprietary as hell (one-on-one)
      • this is the software that the scam artists that cold call you about your “Windows computer being filled with viruses and malware” use to take over your computer
      • that doesn’t imply that it’s evil, just that it’s useful
    • Chris wants to propose using tmux or GNU Screen to share terminals 🙂
    • K12 software (educational group software)
    • Not quite a shared / groupable screen, but we just presented to a conference with OBS, and it worked really well: https://obsproject.com/ [SR]
    • Google meet is pretty analogous to zoom and doesn’t offer extra answers
    • VR rooms that have ‘virtual’ breakout rooms
      • Mozilla hubs doesn’t require VR, allows you to log in with browser (hubs.mozilla.org)
      • https://hubs.mozilla.com/ZSJKAWd/loathsome-wooden-gathering
      • Al SpaceVR (no browser version, goggles required) App that comes with oculus
      • AltSpaceVR accessible with steam client
      • each space has concept of virtual board that can be a board, video or screen

    1.4 Let’s set up an etherpad

    location is May GTALUG EtherPad

    1.5 How do people back up their personal stuff

    • Chris has a horde of little Git repos, anything important gets added to a git repo and pushed places (what does “important” mean???)
    • should automate as much as possible so that we don’t forget to back it up
    • I don’t. I should, but everything is too much hassle or expense. I need something as simple as TimeMachine, but I don’t have bandwidth (or cash) to do a cloud backup [SR]
    • Cronopete claims to be a Time Machine clone for Linux:
    • I have a secondary server, and I have a rsync script that backs up my home directory (and a few others) every night.
    • rclone for encrypted backups with 1 local backup and b2 as remote
    • etckeeper stows /etc in your choice of repos automatically. When you run “apt upgrade”, it automatically checks things in. That doesn’t automatically back up the repo; that also needs to be handled

    1.6 Splitting audio and video streams that are still in sync

    ffmpeg -re -i $(youtube-dl -g -f 96 https://www.youtube.com/watch?v=9Auq9mYxFEE) -f v4l2 /dev/video2 -f alsa default 
    
    • Don’t split the streams
    • Video is fed through puredata
    • this has gotta be within OBS’ remit [SR]
    • use OBS to recombine audio and video stream but this is still a problem
    • a/v delay is not always the same

    1.7 People’s experiences with PiHole

    1.8 GPT harddrives vs Motherboards that do not support GPT

    • The issue might be advanced formatting 512 blocks (legacy) vs 4K blocks (now)
    • Seems to work fine except when it works as a boot device
    • Notes on buying new harddriver for an old system (i.e. Motherboard of 2012 vintage)
    • Try to upgrade BIOS there might be a workaround
    • On a GPT driver you can put fake MBR (older BIOS will see MBR drive, newer MBR will see GPT) This is a horrible hack
      • Refine (website)
        • https://www.rodsbooks.com/
        • lots of information on EFI firmware. Lots of discussion on GPT and Hybrid GPT
        • A lot of details on the website not explained in a beginner-friendly way but it is a great resource
    • Howard’s notes – http://home.eol.ca/~hgibson/Linux.html

    1.9 thoughts about the STL trying to merge in the high perfomance C++ folly library from facebook

    • Link to Folly library: https://github.com/facebook/folly
    • I don’t have a mic but the question is about the issues of using out of stream perfomance libraries to fix the gap caused by the STL
    • There is no RCU or high perfomance spinlocks for example.
    • RCU (read-copy-update)
    • Yes it has that but its not a standard so its a problem as your using a third library and having to merge both.
    • You basically have to right a lot of it by hand.

    1.10 Kubernetes (K8S)

    • Does anyone know what a “service mesh” is? There are systems: Istio, Consul, Linkerd. Service Mesh gets treated as “otta be obvious what this is”
    • In HA, a service mesh is a “meshing” of components so that if one component fails, others will take over immediately

    1.11 Thoughts on these database clients?

    • I’m using the MSSQL one. https://github.com/dbcli (seneca)
      • I’ve been finding typing laggy and it crashes on some commands on certain tables, but at least I don’t end up dealing with FreeTDS [SC}
      • Cannot connect to the MSSQL 2000 server that I still deal with [SC]
    • +1 for DBCLI! (I’m Not Giving My Name To A Machine)

    1.12 Cleaning my Laser printer – HP2605DL (Postscript)

    • It’s a colour printer
    • the colour toner seems to have gone cruddy
    • I wiped yellow and green toner off the plastic paper feed; a new supply emerges from somewhere every time I print a sheet
    • Can’t tell where the reservoir of “crud” is 🙁
    • Have you tried the built-in cleaning tool from the manual (page 131)?
      • Not yet, will do…

    1.13 Curious Calculators