May 2021 - 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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Kurzweil Reading Edge
by Mike Kallies 01 Jul '21

01 Jul '21

Hey Everyone, These came up recently on the list and coincidentally there's a great Youtuber (Techmoan) who just did a piece on the devices, https://www.youtube.com/watch?v=g0jECuwrn_U It's approached as a gadget guy, so no deep dives, but he demos it and gets into a bit of the history and the warts of the aging machines. Interestingly he adds that he's planning future videos on "more recent takes on the same concept" Cool stuff. Mike

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e-reader recommendations
by Trevor Woerner 21 May '21

21 May '21

I'm looking for recommendations for e-readers. Ideally these recommendations would come in the form of "I have used <the following e-readers> and <this> is the one I like best for <these reasons>" ;-) Nice to have features: - be able to read websites (i.e. surf the web) - be able to mirror a screen from my desktop (or act as another monitor) - be able to take notes

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Myanmar military moved early on telecoms
by Warren McPherson 19 May '21

19 May '21

In the months before the Myanmar military’s Feb. 1 coup, telecom and internet service providers were ordered to install intercept spyware that would allow the army to eavesdrop on communications. @f_potkin <https://twitter.com/f_potkin> & @poppymcp https://www.reuters.com/world/asia-pacific/how-myanmars-military-moved-tele…

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help ask that eloquence tts be open source.
by Karen Lewellen 17 May '21

17 May '21

Hi folks, Sharing this here because while tts is indeed apart of some adaptive technology tools, its use in devices serving the general populous is expanding as well. There is an effort to ask Microsoft to make the tts engine Eloquence open source. https://www.change.org/p/microsoft-open-source-eti-eloquence while this can be a matter of opinion, Linux tends to suffer a great deal from poor quality, and complex to configure tts options. granted the link does not work well in lower graphical environments. Still, if this resonates, please share and forward, its one of those areas where adaptive technology and broader technology intersect after a fashion. Thanks, Karen

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Looking for a can shield for an UNO or compatible
by Dave Cramer 14 May '21

14 May '21

Is there a local source for something like MakerFocus CAN-Bus Shield V1.2 <https://www.makerfocus.com/products/makerfocus-can-bus-shield-v1-2> ? Bonus points if it had GPS Dave Cramer

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Re: [GTALUG] "DNS Wars"
by D. Hugh Redelmeier 13 May '21

13 May '21

| From: ac via talk <talk(a)gtalug.org> | which project are you speaking of Our project was FreeS/WAN https://freeswan.org/ The intent was to opportunistically encrypt the internet. Authentication is the hardest part to do. We decided that a system's ID would be their IP address and the system would declare its public key in the reverse domain for that IP address. This was cute. Out of date now because almost nobody controls their reverse domain. Eventually our system worked but almost nobody cared enough to deploy it. Free software! The code lives on for VPNs, but that was certainly not the project's goal. | and do you happen to know if the | various/any RIR have any standardised protocols and/or implementations? No. PS: the blog post included an embadded YouTube video. I finally watched it. Very good. Vixie: "Keynote: DNS Wars: Episode IV A New Bypass" NANOG 2019 https://www.youtube.com/watch?v=LYosersEBoM&t=101s

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Performance Testing in Chrome
by Nicholas Krause 12 May '21

12 May '21

Greetings, So I recall Kevin asking about it but here are some articles on Chrome DevTools testing tools. It's been there for a few years so really there is no excuse for not running your code through it or the audit feature. Not sure about Firefox's internal testing suite off hand: https://developer.chrome.com/docs/devtools/evaluate-performance/ https://developer.chrome.com/docs/devtools/speed/get-started/ Hopefully this helps, Nick

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[GTALUG-Announce] Meeting Today
by hi＠gtalug.org 11 May '21

11 May '21

# Lightning talks and Round Table 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 <a href="mailto:speakers@gtalug.org">speakers(a)gtalug.org</a> to be added to the list of scheduled talks. 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. Due to global pandemic we are going to hold this session via video conferencing. We're going to use jitsi for this meeting: Meeting room url: https://jitsi.flamy.ca/GTALUG ## Location Jitsi meeting ## 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 at board(a)gtalug.org. --- GTALUG Announce mailing list announce(a)gtalug.org https://gtalug.org/mailman/listinfo/announce

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meeting tonight?
by D. Hugh Redelmeier 11 May '21

11 May '21

I don't see an announcement.

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