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     3 s   25   64    1    0.464  -19.446   0.000 .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    .XFAC.          16 s    -  128    0    0.000   +0.000   0.000     3 s   54   64    1    0.283   -4.946   0.000 .XFAC.          16 s    -  128    0    0.000   +0.000   0.000
*   .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 .GPS.            1 u   23 1024    3   72.396   -7.548  79.119   3 u   27 1024    3  112.404  +22.622  40.738
+    2 u   24 1024    3  101.382   -9.729  95.870 .CDMA.           1 u   37 1024    3  106.625  -11.264  97.836    2 u   42 1024    3  133.717  +24.106  39.239
+time.cloudflare       3 u   42 1024    3  111.500  +22.664  38.322
+    2 u   40 1024    3  117.507  -13.853  95.332
+strongbad.voice   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?

a packaging format
Canonical sponsored central app repo
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. – [][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…

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
  • 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: [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 (
    • 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 -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)
      • 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 –

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

  • Link to Folly library:
  • 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. (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

nnn – a terminal-based file manager

nnn, findable at, is a terminal-based file manager written in Go, which claims high performance and has a pretty flexible set of functionalities including:

  • Can spawn your favorite $VISUAL $EDITOR to edit files
  • Bookmarks (haven’t used)
  • Fuzzy searching for files
  • Pin frequently used files/directories
  • Mount and manage archives
  • Lots of plugins to extend its behaviour

I have, several times, scheduled tasks (taskwarrior!) to poke some more at nnn. It seems inevitable to not go anywhere.

Why that is finally occurred to me; the reason is that my workflow that would be most relevant to this takes place inside emacs, in the Dired mode.

There are some neat things in nnn, notably the fuzzy searching, which would lend itself to somewhat more nondeterministic searches for Files Of Interest. However, the learning curve of switching to a dramatically different tool is not to my taste.

If you’re one of the vi crowd, this may be to your taste; it seems interesting. (I was tempted enough to keep it lurking in my task list for a couple months.)

Warring with My Tasks

The local LUG had a talk recently about Task Warrior, which inspired me to give the tool a poke.

I have had excessively fragmentary handlings of outstanding ToDo items, where I have assortedly used:

  • Index cards to note things, but this is really ephemeral; I tend to turf them quickly, and only the most immediate things would get captured here, and evaporate as quickly. These can get clever; I didn’t get enough into that, I’m not hipster enough for that!
  • For a while (and this has gotten to be pretty distant in the past) I used todo.txt to capture things to do. Unfortunately, there’s not much of a synchronization mechanism, so I at one point ran the iOS app on my (still around somewhere) iPod Touch, later on Android phones, with occasional copying onto Unix desktop. But because coordinating versions amounted to doing by-hand git patching, this was way less useful than wanted.
  • For quite some time, I used Org Mode files for my grocery list, syncing between desktop and mobile devices using SyncThing. This was decently viable, actually, allowing me to manage the document on desktop (with a lovely big keyboard and big screen for mass editing) and on mobile device (so the list is handy to mark off purchases). Once in a while, I would push completed items into a side file for posterity. I also copy this data to a Git repository (for arguably “more posterity”); it is not as automated as it ought to be, trying to automate Git checkins was more troublesome than it ought to be.

But in November, at the above mentioned talk, I installed Task Warrior on my phone and decided to give it a try. FYI, I run it in a Termux session on my phone. There do exist a couple of TaskWarrior apps, but I have not yet been able to get them to sync to my taskd server. I am happy enough with the Termux-based CLI access. Perhaps I should set up a web server as an alternative interface? We’ll see…

Overall Configuration

I have the app (apt-get install taskwarrior) installed on a variety of hosts:

  • Work desktop, which syncs against central taskd
  • Chromebook laptop, syncs against central taskd
  • Home server Karush, which hosts taskd and has client syncing against taskd
  • OnePlus 5 (Android phone), where termux hosts the app, syncing against taskd

I installed taskd on a server at home. This was a bit of a pain in the neck; setting up users and certificates is fairly fiddly as also is setup of each client. It took a few tries to get it all working, and I went through a couple of user UUIDs before I was done. It comes with a systemd unit file; I have not thus far had that work, so I have to browse through history (boo, hiss!) to find the right command to restart it properly upon system reboot it took some effort to get that working properly.

One interesting thing I noticed; when syncing got “deranged” and I wound up on a new user UUID, I found that, in order to get things unstuck, I had to edit ~/.task/ Note that this file contains the UUID of the user that it intends to sync against. (I’m not 100% sure; this may be the “local” idea of the UUID of the user…) The removal of the UUID at the top of that file led to the local instance of task generating a new UUID and proceeding.


I basically started out by tossing in all sorts of tasks that popped up, without too much intentionality, just making sure that knowledge about upcoming Things To Do got captured. I wasn’t sure what projects or tags to use; it is out of seeing a bunch of tasks that need to be classified that the patterns will emerge. I am basically just 3 months into this, so while some patterns have emerged, there are plenty more to come.

  • It turns out that tagging with +home and +work is mighty useful, for the simple reason that it allows en-masse deferral of tasks. At the end of the work day, I find it handy to simply defer items to another day thus:
    task +work status:pending wait:tomorrow
    It would probably be valuable to defer things further, so that my list of things to do immediately does not get randomly cluttered.
  • COVID-19 has changed the above a bit; work from home means that the separation is entirely less obvious
  • I have been adding in lots of periodic tasks as they pop up:
    • Paperwork tasks such as filing copies of pay stubs, bank statements, tax documents, and bills of importance
    • Preparations for annual events
    • Reminders for mailing list moderation
  • Some projects have been emerging, but not quickly or well. It is easier to think about adding tags, and occasionally a tag emerges as being important enough to call it a project.
  • I am (still!) not using dependencies nearly much as I probably ought to.
  • As “wishful thinking,” I’d like it if I could have grocery items dependent on a “go to grocery store” task, and have the children pop up as current the moment I arrive at the store and mark that first task done. That also means I’d like it if the children were being “masked” as not ready to proceed (ergo not listed) until I get there.
    • In reviewing Tomas’ presentation, I found A Better Way to deal with this, which is to use contexts. If my grocery items all have +metro as the locational tag (my nearby grocery store is called Metro), then I can define the relevant context:
      task context define metro +metro
      task context metro
      More inclusions and exclusions could be done; in any case, it is clearly useful to use some contexts so when in a particular place, the set of tasks are restricted to those of relevance.
  • Projects (indicated by adding project:taxes.2019 or project:bugzilla.20721 or project:website) are evidently more useful than I had thought, once I start using the dotted notation to allow hierarchical subprojects. They had appeared to be way less useful than labels, but hierarchy changes that. Both are good things (in moderation!) and are good used together.

Future Items

  • Another few months of patterns hopefully leads me to get a bit smarter about how I’m using this, particularly with regards to deferring items I can’t do immediately.
  • I need to get the “sorta graphical” Android client working; need to fight with the configuration to get that working.
    Update 2020-05-07, I finally found documentation that helped me on this… had the crucial aspect that I needed to copy a trio of .pem files (certificate data for my user and for my taskd server) into /Internal Storage/Android/data/kvj.taskw/files/one-of-the-subdirectories
  • I find, regrettably, that I don’t very much like the Android client
  • There are some interesting analytical reports such as task burndown to get some longer term patterns out of it. For that to provide value requires more data collection.
  • I imagine I should be automating some task management, such as having things like the following:
    • TaskWarrior should draw a feed of tasks from bug reports. There’s an extension to pull from Github
    • We’re apparently getting into Scrum work; it would be neat to pull Jira tasks into TaskWarrior automatically
  • There’s an Emacs mode; wait, wait, that’s actually comparatively complete, despite being exceeding brief. It works, and is already useful.
    It probably would be worth extending this to allow operations other than ‘a’ (to add a task) and ‘g’ (to refresh the list), to have a set of interactions one might perform on visible items. The Kubernetes interaction mode for Emacs has some relevant examples.
  • I’m told hooks are interesting, and certainly grasp the broad concept from the way that Emacs uses hooks really really a lot…
    At first glance, it seems less interesting than I had expected…
    • One use case is to automatically commit changes to Git; that is broadly interesting, but I think I can live with that taking place pretty periodically rather than continuously. Especially in that I switch clients a lot, so that keeping consistency would require a lot of Git synchronization.
    • Another usage is to rewrite tasks.
      An interesting example was to change notations, so @projectname would be used to specify project, which is shorter than project:projectname. As above, this needs to run “everywhere” which seems less than convenient. (Again, needs Git repo synchronization, this time for the repo containing the hooks.)


I have been happy enough with my experiences with TaskWarrior, and will be continuing to use it. There are clearly plenty of features I am not using yet, some of which may make sense to poke at further.

Subversion “deprecation”

I was a bit tickled by the characterization I saw today in the new Subversion release, describing the deprecation of version 1.5:

The Subversion 1.5.x line is no longer supported. This doesn't mean
that your 1.5 installation is doomed; if it works well and is all you
need, that's fine. "No longer supported" just means we've stopped
accepting bug reports against 1.5.x versions, and will not make any
more 1.5.x bugfix releases.

They aren’t telling us the world will end for anyone using version 1.5, just that they don’t intend to provide support anymore.

Which seems like a fine thing. Version 1.5 is 3 years old, and, when they seem to be releasing about a version per year (1.0 in 2004, 1.7 in 2011), 3 years of backwards support doesn’t seem dramatically insufficient. Particularly if, when support goes away, you’re not inherently doomed!

Music Playing

My latest “musical experiment” is with Clementine, which was recently added to Debian.

I should note things that I have used in the past, and some areas of past pain:

Which has often been nice enough, but which has grown long in the tooth.
Which takes the desirable step of being a client/server system which admits the availability of a bunch of backends. I have, when using it, tended to prefer the shell backend.
An “all singing, all dancing” option…

  • It uses KDE, which I’m historically not terribly keen on
  • It has libraries that are evidently clever enough to pull music off my iPod Touch as long as it’s plugged into a USB dock
  • It has the “KDE integration” that seems to want to have widgets integrating into some “KDE-compliant” window manager. I’m running StumpWM, which is decidedly not a KDE thing, so controlling Amarok always seems like a bit of a crapshoot…
  • I have played a bit with the “playlist” functionality; it hasn’t yet agreed with me…

At any rate, I saw Clementine listed as “new in Debian,” so thought I’d take a peek. I’m liking what I see thus far:

  • Onscreen widgets for all the sorts of things that need to be controlled, including
    • Managing music library, so as to add things
  • Like Amarok, it can see my iPod whenever it’s plugged in, and can play that music through the computer
  • It easily grabbed album covers (I’m not sure what service it’s using) for most of my music
  • Onscreen controls seem pretty reasonable, though I kind of wish the volume control was larger, as that’s something one wants most frequently to fiddle with.
  • There’s a cool visualization widget (think “equalizer”)

Seems pretty likable thus far…