April 2019 - Talk - lists.gtalug.org

war story: power failure makes CentOS system unbootable
by D. Hugh Redelmeier 30 Sep '22

30 Sep '22

tl;dr / spoiler: change fstab so that /boot/efi is not automatically mounted. See the recommendation at the end of this message. My gateway computer is a little PC running CentOS. It does not come back after a power failure. The reason (as best I can tell) is interesting and I think that I have a fix. My system is UEFI. It boots from a UEFI system partition, known as /boot/efi to Linux. If this gets corrupted, it won't boot. It is a VFAT partition. On my gateway (a Zotac Zbox RI321, a cute little box with two ethernet ports), the UEFI firmware apparently won't boot if the dirty bit is set in the system partition. CentOS normally runs with /boot/efi mounted. So when the system isn't shut down cleanly, the dirty bit will be on. Consequence: the system is not going to boot after a power failure. Odd observation 1: if I put a live Fedora 25 USB stick in the system and try to boot in this otherwise-unbootable state, CentOS boots from the main disk. So this really looks like a firmware bug/quirk. Odd observation 2: fsck doesn't seem to automatically fix the system partition. Once CentOS 7 booted, I dismounted /boot/efi and did an fsck on it. $ sudo fsck /dev/sda1 fsck from util-linux 2.23.2 fsck.fat 3.0.20 (12 Jun 2013) 0x25: Dirty bit is set. Fs was not properly unmounted and some data may be corrupt. 1) Remove dirty bit 2) No action ? 1 Leaving filesystem unchanged. /dev/sda1: 16 files, 2420/51145 clusters Googling got me to <https://www.centos.org/forums/viewtopic.php?t=50917> In particular, this advice seemed quite good: ==== recommendation ==== Two other changes I recommend for UEFI systems, to each OS's /etc/fstab. - For the /boot/efi mountpoint, add the mount options x-systemd.automount,noauto - Change fs_passno (last column) to a 1 or 2; the canonical fstab instructions suggest 2, but systemd treats 1 and 2 as the same. The first change means the EFI System partition will not be automatically read-write mounted at boot time; it's a bad idea this is the default because it puts the ESP at risk especially if ther are crashes, FAT has no journal and will therefore always be marked dirty in such a case; no other UEFI OS mounts the ESP by default. Second, if anything tries to access /boot/efi (read or write), systemd will automatically mount it, and because of the fs_passno 1 or 2, it will fsck it first and that fixes and clears the dirty bit in case it's set. Right now without these changes, it's just a matter of having the right number and bad timing of crashes to render the EFI System partition corrupt.

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Ontario Bill 72: "Right to Repair"
by D. Hugh Redelmeier 26 May '19

26 May '19

This is a private member's bill so it is unlikely to pass. <https://www.cbc.ca/news/technology/what-on-earth-newsletter-right-to-repair…> <https://www.ola.org/en/legislative-business/bills/parliament-42/session-1/b…>

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a simple security solution?
by Karen Lewellen 17 May '19

17 May '19

Hi everyone, I do hope to ask this clearly. what I desire is a method of confirming if someone enters or approaches my flat without my knowledge. Ideally there would be a small camera, even a phone just for this role might work, with at the absolute best a notification sent via voice or e-mail that the feature is active..I hope this makes sense. Perhaps it activates when someone opens my downstairs door, letting me know? Perhaps an alarm, perhaps not. I might also dedicate a laptop to this role, but the most important thing is that I am notified, the setup calls my own phone number land line for example, or sends me an e-mail. I have no way to get a text message, unless this message is spoken. If I am not being clear let me know. Range need not be profoundly large either. Ideas? Kare

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Jobs at Epson Canada
by William Park 13 May '19

13 May '19

Hi all, Three (3) jobs recently opened up at my company, Epson Canada. And, they are asking help from employees in search for candidates. > 1. Machine Learning Research Scientist (Robotics Control) for EDGE This is R&D robotic 2nd floor. The focus is more on algorithm, but Linux is part of discussion during lunch. > 2. Firmware/Embedded Developer for RTSC > 3. Software Technical Support Representative for RTSC These two are in my group 1st floor, and definitely Linux related. If you're interested or know of someone who is interested, then let me know and I can send you more "official" details. Eventually, you'll be applying directly. -- William Park <opengeometry(a)yahoo.ca>

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Free printer and scanner
by William Park 28 Apr '19

28 Apr '19

Hi all, I have 1. Epson WorkForce WF-2650 -- all-in-one printer 2. Epson WorkForce DS-560 -- color document scanner collecting dust in my basement. They were demo units used by Marketing department, and I won them in raffles. Anyone want them? -- William Park <opengeometry(a)yahoo.ca>

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of routers and access points
by David Mason 27 Apr '19

27 Apr '19

I had a setup where my modem was connected to my gateway Linux box which did routing, DHCP, DNS, etc. and was also connected to a switch which was connected to a WiFi router being used as an access point. This is too brittle for my tastes, as other members of my family can’t resolve problems with it. Something went wrong so I have temporarily reconfigured it so the WiFi router is connected directly to the modem, but this doesn’t let the WiFi clients connect to the Linux boxes or other hard-wired machines or let them connect to the internet. (I could connect the other devices to the router, but for WiFi propagation reasons, the WiFi router is far away from all the other devices, so this is not ideal.) So I was thinking of getting a https://www.canadacomputers.com/product_info.php?cPath=27_1046_363&item_id=… router and connecting to that the Linux box (which would still do DHCP (possibly) and DNS, the router configured back as an access point (or a POE access point such as https://www.canadacomputers.com/product_info.php?cPath=27_1056_356&item_id=…, as well as the other wired devices. Thoughts? Thanks. ../Dave

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[GTALUG-Announce] Round Table Q&A Session
by hi＠gtalug.org 23 Apr '19

23 Apr '19

<https://gtalug.org/meeting/2019-05/> # Round Table Q&A Session ==== A Round Table Q&A Session is where we take questions from the audience, and the audience discusses and attempts to answer those questions from their own knowledge. It's a great way to meet fellow members of our community and discover the skill sets we each bring to the table. There will be no video recording during the session. ==== ## Location George Vari Engineering and Computing Centre 245 Church Street, Room 203 Ryerson University <https://goo.gl/maps/16oJ2> <https://www.openstreetmap.org/way/23447525> ## Schedule * 6:00 pm - Please discuss on the general mailing list (i.e. <talk(a)gtalug.org>) where you want to go for dinner. * 7:30 pm - Meeting and presentation. * 9:00 pm - After each meeting, a group of GTALUGers move to The Imperial Pub (54 Dundas St East) for refreshments and more socialising. # 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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Installing Anaconda with Python 3 on 32 bit linux (Ubuntu ver 16.04 )
by 90ur1 90ur1 20 Apr '19

20 Apr '19

I just downloaded and installed Ubuntu 16.04 on my IBM thinkpad edge . And then downloaded and tried to install Anaconda. The installer gave me an error that the binary is 64 bit while my computer is 32 bit. So I am trying a 32 bit linux package for Anaconda It is not listed on the downloads page. If you have used it , can you direct me to the link Thanks! Gouri

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April 2019 meeting video
by Alex Volkov 19 Apr '19

19 Apr '19

Hey Everyone, April 2019 meeting video -- Linux Unhatched Learning Circles at Toronto Public Library with Larysa Essex Is available here -- https://youtu.be/lvZ3gCzrXak Alex.

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Toronto BSP on Saturday, April 27
by Alex Volkov 18 Apr '19

18 Apr '19

Hello GTALUGers! Debian Bug Squashing party is happening in Toronto on Saturday, April 27 at 9am the Mozilla Toronto office. More details on this event are here -- https://wiki.debian.org/BSP/2019/04/ca/Toronto If you would like to participate please email me to (alex at flamy.ca) and I would add you to the list of participants. A Bug Squashing Party is a come-together of Debian Developers and Debian enthusiasts on a specified timeframe where these persons try to fix as many bugs as possible. I'm organizing this event with Sergio and Samuel and we've invited anarcat and invite him to come to Toronto and give his "Packaging 101" talk and has kindly 99%-accepted. Other than the presentation we're planning to introduce as many people as possible to software packaging in debian and squash as many bugs as we can. If Bug Squashing Party is something new, please read this beginners HOWTO -- https://wiki.debian.org/BSP/BeginnersHOWTO Alex.

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