September 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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Has anybody used the windowsfx linux distrio?
by Alvin Starr 24 Sep '21

24 Sep '21

It looks kind of interesting for those who are comfortable with Windows and are afraid of Linux. Comments, hints and/or warnings would be appreciated. -- Alvin Starr || land: (647)478-6285 Netvel Inc. || Cell: (416)806-0133 alvin(a)netvel.net ||

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Vaccination Receipts on Linux
by D. Hugh Redelmeier 23 Sep '21

23 Sep '21

The Ontario Governement emailed us Vaccination Receipts shortly after we were vaccinated. As of Sept 22, we will need to show them some places if we want access. When I go back to that email, I find that it is defective. You cannot read the PDF from my MUA (Alpine on Linux), and I suspect that this is true for any Linux or UNIX MUA. Perhaps also for Apple MUAs. The reason is that the PDF is sent as an attachment, with the wrong type specified in the attachment's headers: Content-Transfer-Encoding: base64 Content-Type: text/plain;charset=utf-8 Content-Disposition: attachment;filename=Dose_Admin_...pdf" On POSIX systems, attachments with Content-Type "text", have CR LF sequences replaced by NL. I was able to make it work by manually editing my mailbox, changing the Content-Type header to: Content-Type: application/pdf

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apropos of DCB's lightening talk on bad diagnostics, a Windows war story
by D. Hugh Redelmeier 22 Sep '21

22 Sep '21

A poet friend's Windows notebook ceased working and Windows could not get up again. A couple of days work did not result in a working system. He was going to solve the problem by buying a new machine. I volunteered to attempt to fix his machine. I investigated the system (using a live Fedora stick). I found that his files were gone and that the disk wasn't 100% happy. I fixed it by copying /dev/zero to the whole raw drive. (There were 8 relocated sectors, not a strong sign that the disk is deteriorating quickly.) Whereas before my fix, a short drive-self-test failed, afterwards it passed. The next step was to make a bootable Win 10 installation disk. A bootable Win 10 installation disk is not as simple as a bootable Linux disk. It won't perform as a Live system. It isn't made by dding a .iso to the USB flash stick. On another Windows box, download the Media Creation Tool. Run it, asking it to create an installation stick. It downloads Windows, and uses the files to build the installation stick. This failed for me. I'm not alone. There are many postings by confused users. I found many many suggestions of work-arounds, but no convincing theory that any of them worked. At the start of this thread, you'll see the truly useless error pop-up: <https://answers.microsoft.com/en-us/windows/forum/all/media-creation-tool-e…> Windows 10 Setup There was a problem running this tool We're not sure what happened, but we're unable to run this tool on your PC. If you continue experiencing problems, reference the error code when contacting customer support. Error code 0x80042405 - 0xA001B There is no evident customer support. Just fora full of ignorance. This problem (or at least this symptom) has been around for years. For no good reason, I reformatted the USB stick and ran the MCT again. And it worked. At the cost of having downloaded all of Win 10 twice. MCT is too stupid to save its work. Evan may like Windows, but my modest experiences with it are often unpleasant. Now I'm onto the pleasures of installing Win 10 on a slow machine without an SSD. This is an area where Linux is much much more streamlined.

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[probably offtopic] e-sign solutions
by Evan Leibovitch 20 Sep '21

20 Sep '21

Hi all. I have a short-term need for an e-signing facility. There are a few free ones (digisigner.com) but I'm not familiar with them, and I'm not prepared to pay Adobe $40/mo for justa doc or two. Any recommendations? Anything to avoid? Thanks! Evan Leibovitch, Toronto Canada @evanleibovitch / @el56

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[GTALUG-Announce] Meeting Tomorrow
by hi＠gtalug.org 13 Sep '21

13 Sep '21

https://gtalug.org/meeting/2021-09/ # 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 to speakers(a)gtalug.org to be added to the list of scheduled talks. We're going to use Zoom for this meeting: Join Zoom Meeting: https://us02web.zoom.us/j/83647888809?pwd=RHVwZndZY1dZOHRlcE9ER25QUkkrZz09 Meeting ID: 836 4788 8809 Passcode: 804603 One tap mobile +16473744685,,83647888809#,,,,*804603# Canada +16475580588,,83647888809#,,,,*804603# Canada Dial by your location +1 647 374 4685 Canada +1 647 558 0588 Canada +1 778 907 2071 Canada +1 204 272 7920 Canada +1 438 809 7799 Canada +1 587 328 1099 Canada Find your local numberhttps://us02web.zoom.us/u/klYT1laDI ## 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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Linux 3D graphics stack meeting video (August 2021)
by Alex Volkov 13 Sep '21

13 Sep '21

Hello Everyone, Here's the video from our last month meeting on August 10, 2021. The Linux 3D graphics stack with Alyssa Rosenzweig -- https://youtu.be/0F0aQ2eympI Alex.

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Fedora 34 with EFI boot on Raspberry Pi 4
by Stewart Russell 13 Sep '21

13 Sep '21

At last night's Raspberry Pi meetup, Chris Tyler demonstrated Fedora 34 (aarch64) on Raspberry Pi 4. It's supposed to be a fully supported distribution, although the documentation hasn't quite caught up. It looked pretty neat, and I might be tempted to try it. I've been a Debian user this entire century so far, though, so there might be some friction. Audio over HDMI isn't supported yet, which will mean some hardware juggling for me. The EFI boot hasn't made it to other distros on Raspberry Pi yet, so the installation has to be from a raw image or Fedora's arm-image-installer tool. Fedora Workstation is here: https://getfedora.org/en/workstation/download/ and you'll be wanting the aarch64 raw image. cheers, Stewart

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Anyone know of a service to see if someone's pretending to be me?
by David Collier-Brown 12 Sep '21

12 Sep '21

My company just found a fake instance of themselves, so I wonder what folks do to detect them? I know politicians suffer impersonation a lot, but I don't know who's out there helping people and companies find and shut down the scammers. --dave -- David Collier-Brown, | Always do right. This will gratify System Programmer and Author | some people and astonish the rest davecb(a)spamcop.net | -- Mark Twain

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Anyone know of a service to see if someone's pretending to be me?
by David Collier-Brown 11 Sep '21

11 Sep '21

My company just found a fake instance of themselves, so I wonder what folks do to detect them? I know politicians suffer impersonation a lot, but I don't know who's out there helping people and companies find and shut down the scammers. --dave -- David Collier-Brown, | Always do right. This will gratify System Programmer and Author | some people and astonish the rest davecb(a)spamcop.net | -- Mark Twain

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