March 2021 - Talk - lists.gtalug.org

[GTALUG-Announce] Meeting on Tuesday, April 13 at 07:30 PM
by hi＠gtalug.org 24 Mar '21

24 Mar '21

<https://gtalug.org/meeting/2021-04/> # Windows subsystem for linux with Evan Leibovitch After one too many times fighting with PulseAudio and video drivers and having printers and scanners that will NEVER work with Linux, I gave up my dual boot laptop and desktop and have loaded Win 10 on both. Turns out, things run faster too, even open source apps like Handbrake which take advantage of the GPU to do its video decoding while Linux can't do that. But the story is not done. I installed Windows Subsystem for Linux and now have a fully running Kubuntu as a VM when I want it. And there are some interesting tools such as Windows Terminal in which you can have a Linux terminal shell next to a tab with Windows PowerShell. # Lightning talks This is GTALUG's version of an un-conference, a loosely structured short talks emphasizing the informal exchange of information and ideas between participants, rather than following a conventionally structured GTALUG meetings. If you already have a topic in mind please send an email to speakers(a)gtalug.org to be added to the list of scheduled talks. ## Location Zoom meeting. TBD ## Schedule * 7:30 pm - Meeting and presentation. # Code of Conduct We want a productive happy community that can welcome new ideas, improve every process every year, and foster collaboration between individuals with differing needs, interests and skills. We gain strength from diversity, and actively seek participation from those who enhance it. This code of conduct exists to ensure that diverse groups collaborate to mutual advantage and enjoyment. We will challenge prejudice that could jeopardise the participation of any person in the community. The Code of Conduct governs how we behave in public or in private whenever the Linux community will be judged by our actions. We expect it to be honoured by everyone who represents the community officially or informally, claims affiliation or participates directly. It applies to activities online or offline. We invite anybody to participate. Our community is open. Please read more about the GTALUG Code of Conduct here: https://gtalug.org/about/code-of-conduct/. If you have any questions, comments, or concerns about the GTALUG Code of Conduct please contact the GTALUG Board @ board(a)gtalug.org. --- GTALUG Announce mailing list announce(a)gtalug.org https://gtalug.org/mailman/listinfo/announce

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risc-v seems to be gaining traction
by Warren McPherson 23 Mar '21

23 Mar '21

Amazon gets behind free rival to Arm’s microchips https://www.telegraph.co.uk/technology/2021/03/20/amazon-gets-behind-free-r… I didn't get beyond the paywall, but it sounds like the article is based on ads that suggest Amazon is looking to hire engineers with risc-v experience in response to NVIDIA buying Arm. I thought that was an interesting development.

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War Story: debugging remote port access
by Giles Orr 22 Mar '21

22 Mar '21

A couple quick details: - I believe the TLUG list was down: I sent a message 12 March which didn't appear, and GMail eventually informed me it couldn't deliver it. Two days later it told me it had been trying all along and had given up (I emailed Alex and Scott) - I'm borrowing Hugh's "War Story" format ... remember, imitation is the sincerest form of flattery This is the problem I emailed the list about, but I've now solved it. It's slightly embarrassing, but may be helpful to others. I have a local Samba and MPD server running on a Raspberry Pi 2. This has run far better than I had expected for nearly two years. But because of the USB2 ports on the Pi 2, data transfers to and from it are slow. I configured a Pi 4 as its replacement, but I couldn't finish because after I installed MPD I couldn't access it remotely. MPD is the "Music Player Daemon", but the only important part of this is it offers access on port 6600. On the Pi 2 (which has the older GUI Raspbian on it), I just installed MPD and it worked - according to my notes. I didn't bother with a firewall. On the new machine (Pi 4 with USB3 and Raspberry Pi OS Lite) with MPD running, I could access MPD locally with: $ mpc status volume: n/a repeat: off random: off single: off consume: off 'mpc' is the command line client for MPD, and the response you see above is the correct one when MPD is idle. But as soon as I changed to pseudo-remote, or actually remote: $ mpc --host=pi44.local status mpd error: Connection refused That's without a firewall. I thought perhaps the new Raspberry Pi OS Lite might have helpfully provided some iptables/netfilter rules, and I figured UFW would help: # apt install ufw # ufw enable # ufw allow 6600 This changed nothing about the behaviour of 'mpc' (although it did break Samba ... fixed by opening ports 137, 138, 139, and 445). I dragged out 'telnet' to connect to the local port: all that did was prove that I can access MPD locally but not remotely (MPD responds "OK MPD 0.21.4" when you're able to connect). ----- Finally I figured it out. When I told a co-worker, he got it right away, so I suspect many of you will have too. I said above that it "just worked" on the original Pi, but I suspect that's not true. I take notes when I install software, but I failed to note one change I'm fairly sure I made ... What I finally remembered is that almost any service can be configured to listen to "localhost" only. Remembering that, I found the single critical line in /etc/mpd.conf: bind_to_address "localhost" I compared that to the older Pi, which says: bind_to_address "0.0.0.0" For those not aware, "0.0.0.0" is short for "listen on all interfaces," while "localhost" reasonably enough means "listen only to connections coming from the local machine." This is a common thing in servers and I should have remembered sooner. Restarted MPD and all is good. At least I have a firewall now ... -- Giles https://www.gilesorr.com/ gilesorr(a)gmail.com

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Importing mbox into Thunderbird?
by William Park 22 Mar '21

22 Mar '21

I'm beginning to like Thunderbird. It replaces fetchmail, procmail, sendmail, mutt, and vim for mailing. I miss vim, though. Now, the question on hand... I have lots of "mbox" format files of old emails. How do I import into Thunderbird? Online talks about "Import MBOX file" under "Tools". But, mine (68.12.0) don't have such entry.

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war story: read you kernel log (dmesg) once in a while
by D. Hugh Redelmeier 20 Mar '21

20 Mar '21

[One reason for this message is to test if the mailing list is working. I haven't seen a new message in a 10 days.] dmseg command ============= The dmesg command shows you the kernel log. It takes the log from the kernel itself. It is stored in a circular RAM buffer, so you can still read it if the normal logging system isn't working. This buffer is a fixed size so older messages can get pushed out by newer ones if there is enough logging going on. You can get more info on Fedora by journalctl -b but it isn't limited to kernel messages. It does colour-code messages based on severity, so that's a nice plus. Since this log typically goes to disk, it tends to be complete. Oh: the -b flag means: start from the most recent boot -- logs can go back months and years. As an old timer, my first instinct is to use dmesg. looking at kernel messages ========================== dmesg | less -i dmesg pours out a lot of lines. less is a good way of navigating this log. The -i makes searches within less case-insensitive. The Linux kernel is meant to log problems and move on. This means that there can be problems that you don't even know about because all looks well. I think it pays to once in a while look for problems reported in the log. A lot of messages will be inscrutable. If they intrigue you, investigate them. Here's one I noticed recently on one of my systems. It's been there for the whole life of the system, but I never noticed. [ 2.545003] ata1: SATA link up 6.0 Gbps (SStatus 133 SControl 300) [ 2.545482] ata1.00: supports DRM functions and may not be fully accessible [ 2.545554] ata1.00: READ LOG DMA EXT failed, trying unqueued [ 2.548363] ata1.00: disabling queued TRIM support [ 2.548370] ata1.00: ATA-9: Crucial_CT240M500SSD1, MU05, max UDMA/133 [ 2.548376] ata1.00: 468862128 sectors, multi 16: LBA48 NCQ (depth 31/32), AA [ 2.551973] ata1.00: supports DRM functions and may not be fully accessible [ 2.554812] ata1.00: disabling queued TRIM support [ 2.558006] ata1.00: configured for UDMA/133 Look at "disabling queued TRIM support". What's that about? - TRIM is a useful feature in SSDs. It allows the OS to advise the SSD that chunks of the filesystem are no longer needed (eg. deleted files). This helps the SSD's wear-levelling firmware's garbage collector. It should help speed up the SSD and add to its lifetime. - Even without queued TRIM, TRIM can still be accomplished. Queued TRIM is some higher-performance variant (I haven't investigate). But what's up with this message? Googling got me to <https://bugzilla.kernel.org/show_bug.cgi?id=71371> Very useful. - apparently my SSD (a Crucial M500) had buggy firmware, leading to corruption in some cases. Including queue TRIM - Crucial released new firmware (in 2015) <https://www.crucial.com/support/ssd-support/m500-support> - my SSD has this firmware (MU05), as reported in the dmesg output - even after the update, M500's screw up queued TRIM - the Linux kernel embeds all this wisdom and it blacklists queued TRIM on my box I spent an hour investigating this. There was no effect, except that I learned a few things. Linux just does the right thing. I do recommend also looking at journalctl output because it highlights things that it thinks are of particular interest.

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[GTALUG-Announce] Meeting Today
by hi＠gtalug.org 10 Mar '21

10 Mar '21

https://gtalug.org/meeting/2021-03/ # MySQL High Availability Stack with Zoom meeting In this presentation Peter will present a high availability stack that has recently risen in popularity in the MySQL community. By using Orchestrator, Proxysql, and Consul, you can have greater confidence in the overall ability of your data platform. this session via video conferencing. ## Location We're going to use Zoom for this meeting: Join Zoom Meeting: https://us02web.zoom.us/j/85058613249?pwd=M0ZjSXl1YjVobTh4VmRhV2h0WEZ0QT09 Meeting ID: 850 5861 3249 Passcode: 149625 ## Schedule * 7:30 pm - Meeting and presentation. # Code of Conduct We want a productive happy community that can welcome new ideas, improve every process every year, and foster collaboration between individuals with differing needs, interests and skills. We gain strength from diversity, and actively seek participation from those who enhance it. This code of conduct exists to ensure that diverse groups collaborate to mutual advantage and enjoyment. We will challenge prejudice that could jeopardise the participation of any person in the community. The Code of Conduct governs how we behave in public or in private whenever the Linux community will be judged by our actions. We expect it to be honoured by everyone who represents the community officially or informally, claims affiliation or participates directly. It applies to activities online or offline. We invite anybody to participate. Our community is open. Please read more about the GTALUG Code of Conduct here: https://gtalug.org/about/code-of-conduct/ If you have any questions, comments, or concerns about the GTALUG Code of Conduct please contact the GTALUG Board @ board(a)gtalug.org --- GTALUG Announce mailing list announce(a)gtalug.org https://gtalug.org/mailman/listinfo/announce

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Raspberry Pi
by Aruna Hewapathirane 08 Mar '21

08 Mar '21

Hello, Does anyone have a Raspberry Pi lying around you no longer need ? Thanks - Aruna

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How Linux is Built - YouTube
by James Knott 08 Mar '21

08 Mar '21

I came across this today. While the numbers are a bit dated, this video can help explain a bit about Linux to others. https://www.youtube.com/watch?v=yVpbFMhOAwE

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Which NAS harddisk? -- Seagate or Western Digital
by William Park 08 Mar '21

08 Mar '21

Hi, 2 of my harddisks are failing, so I need to buy something fairly soon. I haven't bought a harddisk for a long time. Has Seagate improved their quality? Or, should I go with Western Digital as I usually do?

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Linux Foundation and RISC-V International launch free RISC-V training classes | ZDNet
by Ivan Avery Frey 07 Mar '21

07 Mar '21

Interesting stuff https://www.zdnet.com/article/linux-foundation-risc-v-international-launch-… Ivan.

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