November 2018 - Talk - lists.gtalug.org

war story: power failure makes CentOS system unbootable
by D. Hugh Redelmeier 29 Sep '22

29 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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good deal on netbook; war story: putting Fedora on it
by D. Hugh Redelmeier 30 Nov '18

30 Nov '18

I recently bought an Acer Spin 1 SP111-31-P95J refurbished netbook. <https://www.canadacomputers.com/product_info.php?cPath=710_374&item_id=1174…> So far, I quite like it. Those are gone but a slightly inferior model is available for a better price ($200): <https://www.canadacomputers.com/product_info.php?cPath=710_374&item_id=1201…> Why should you consider this: + nice size (11.6") and weight + FullHD (i.e. 1920x1080) IPS screen (IPS makes the display a lot better). Some people think that this resolution is too high for this size. I like it a lot. It's a matter of personal taste so don't take my word for it. FullHD + IPS is quite rare on this class of machine and even more rare at this price. + no fan! + folds almost 360 degrees (I don't care) + 4G RAM. That's twice what the cheapest netbooks have had. I find that it makes a big difference in Firefox (at least the way I use it) + 64G eMMC (disk). That's twice what the cheapest netbooks have. It should even be enough for a dual boot Win 10 / Linux system but it isn't generous for dual-boot. It's plenty for Linux. eMMC is slower than SATA of NVMe SSDs. Like most netbooks these days, the eMMC cannot be upgraded. - CPU is only a Celeron N3350 (dual core). That's good for electricity consumption and cooling but not a powerhouse for computation. + the Battery last quite some time -- way more than 4 hours. + supports 802.11ac + it seems to have been refurbed by the manufacturer and has a full year warranty. Mine sure looked as if it was never used. This model isn't current so they might just have been store returns. + 1 x USB 3.0, 2 x USB 2.0 - no ethernet ================ War Story ================ Adventures installing Linux on this netbook (condensed version). a) freshening up Windows and firmware After first boot, I did all updates. This requires you toask several times for updates since it will install a bunch and (incorrectly) say your system is up to date. Don't believe it. I updated the firmware too. This requires Windows, as far as I can tell. You have to hunt for the update on the Acer site. This whole process is excruciatingly slow and requires way too many user interventions. Allocate a day to babysit it. Don't bother with the Windows updates if you are just going to blow Windows away. But I would do the firmware update in any case. b) booting a live Fedora 29 installation medium Note 1: this thing should be used as a modern UEFI system. I don't even remember whether there is an option for legacy emulation (i.e. a CSM and support for an MBR system disk). Note 2: a number of useful settings in the firmware setup page are only enabled if you set an administrator password (you set it in the firmware setup page). A Fedora live USB stick is made by downloading the .iso file and dd-ing it onto the raw USB drive. The Acer just will not boot such a stick. Apparently the same thing happens with an Ubuntu installation disk. Linuxium (that's his nom de guerre) has a tool that apparently doctors such a USB to be bootable. He says that this is a generic Apolo Lake problem but I am skeptical. I think that it is an Insyde Firmware bug. My solution was to burn a DVD from the .iso and boot from that. I could do this because I have an external DVD drive. Note: the image is too large for a CD. c) making room on the disk When installing Linux on a Windows system to create a dual boot system, you need a way to divide disk space. - Windows needs at least 32G of disk; a nice Linux needs close to that too. - Windows comes with a tool that can shrink an NTFS parition. Unfortunately it is unwilling to shrink down to 50% or less. I think that is because certain metadata is smack dab in the middle of the filesystem and is marked as unmovable. - I use gparted to change NTFS partition sizes, especially when Windows won't. It seems to damage the FS but if you immediately reboot Windows after resizing, Windows will repair the damage. This time, when I rebooted Windows after gparted-resizing, Windows could not fix the NTFS partition. I gave up and blew Windows away. After all, I wasn't really going to use it and the disk space would be better used by Linux. I should have made a re-installation disk before I resized the partition, but I did not. d) installing Linux No problem. e) booting the installed linux I placed Linux ahead of Windows in the boot sequence. But the firmware always altered it to put Windows first. Crazy. Especially when there is no Windows (but I had left bits of it in the EFI System Partition (/boot/efi)). I could hit F5 on boot and specify booting Linux, but this is silly. My crude fix was to rename the Microsoft directory on the EFI System Partition to "Macrosoft", thereby hiding it from the bootloader.

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Newegg deal on T450
by William Park 26 Nov '18

26 Nov '18

Hi all, I bought refurbished T450 from Newegg for $315. <https://www.newegg.ca/Product/Product.aspx?Item=N82E16834847378&ignorebbr=1>Fast delivery. Plastic (between RJ-45 and USB port) at the right side is broken, hinting that it was disassembled at some point. Quick overview: - 1600x900 screen is ok - all keys and ports work - SSD is 256GB Samsung, and it seems to be ok - both batteries (there is 1 external, so the other one must be internal) are charging to 100%, though not sure if it means "designed capacity". - Windows Subsystem for Linux (Ubuntu) works - Hyper-V (Ubuntu) works It's out of stock, now. But, there is HD version for $310. <https://www.newegg.ca/Product/Product.aspx?Item=N82E16834847377&ignorebbr=1> --William

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Unix approaching 50
by Christopher Browne 26 Nov '18

26 Nov '18

As Unix approaches its 50th anniversary, some folks have assembled a site where you can access amazing simulations of the early days... This has simulations of various editions of Unix, including, it would appear, "version 0," aka UNICS https://unix50.org/ SDF Public Access UNIX System presents ... /~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/ /~/~ H Y S T E R I C A L ~ U N I X ~ S Y S T E M S ~/~/ /~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/~/ [a] UNICS (Version Zero) PDP-7 Summer 1969 [c] Fifth Edition UNIX PDP-11/40 June 1974 [d] Sixth Edition UNIX PDP-11/45 May 1975 [e] Seventh Edition UNIX PDP-11/70 January 1979 [f] Research UNIX 8 VAX-11/780 1981 [g] AT&T UNIX System III PDP-11/70 Fall 1982 [h] AT&T UNIX System V PDP-11/70 1983 [i] AT&T UNIX System V 3b2/400 1984 [j] 2.11 BSD PDP-11/70 January 1991 [q] QUIT (and run away in fear!) User contributed tutorials are at https://sdf.org/?tutorials Also worth consulting include... https://github.com/dspinellis/unix-history-repo https://lwn.net/Articles/725297/ -- When confronted by a difficult problem, solve it by reducing it to the question, "How would the Lone Ranger handle this?"

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Work in Progress: UltraHD / HDMI 2.0 from older computers; interesting KVM
by D. Hugh Redelmeier 25 Nov '18

25 Nov '18

I have a number of Haswell-based computers that I'd like to use to drive UltraHD (mistakenly called 4k) monitors. (Haswell is the generation of Intel Core processors with numbers like 4nnn, but also a number with others with branding like "Celeron" and some oddball number.) I think all/most of my DisplayPort ports are actually DisplayPort++. That makes it easy to support FullHD (1920x1080 or x1200) HDMI with an inexpensive cable. My UltraHD TV that predates HDMI 2.0 can run at 3840 x 2160 @ 30Hz. To drive it, I use an Nvidia GTX 650. But that won't support 60Hz at that resolution. DisplayPort output from a Haswell processor will support 3840 x 2160 @ 60Hz. But TV's don't have DisplayPort inputs, and UltraHD TVs are generally cheaper than UltraHD monitors. (I won't speak of problems like chroma subsampling, colour depth, sound signals.) I've now found that there are DisplayPort to HDMI 2.0 converters that are a lot less expensive than video cards. They are not dirt cheap but they seem quite useful. They are "active", unlike DisplayPort++ to FullHD HDMI converters. <https://www.amazon.ca/Plugable-DisplayPort-Supports-displays-3840x2160/dp/B…> <https://www.primecables.ca/p-362076-cab-24270-displayport-12a-to-4k-at-60hz…> This works for UltraHD at 30Hz and is a little cheaper: <https://www.primecables.ca/p-362078-cab-12781-displayport-12a-to-4k-hdmi-ac…> (Today, there is a site-wide 20% off for primecables.ca so it there models are cheaper than the Plugable one on Amazon.ca. I have no idea if one is better. Buying directly from Monoprice is cheaper until you factor in shipping and cross-border issues.) Here's Another reason why I want to use HDMI 2.0 instead of DisplayPort. I could really use a KVM switch (Keyboard / Video / Mouse) to allow multiple computers to be controlled by one keyboard, mouse, and monitor. KVMs are either stuck in the VGA era or are very expensive. I've found a 4-port KVM that supports HDMI 2.0 that isn't impossibly expensive: <https://www.amazon.ca/gp/product/B07G883R35> ($100, but there is a box to click to reduce the price by $10. I'm not sure why I wasn't charged HST. Is this something to do with new de minimus rules with the USMCA (NAFTA replacement)? But I wouldn't think that it is in effect.) (Apparently the box-to-tick price reduction is to fool scrapers like <https://ca.camelcamelcamel.com/>) Here's an article that I found useful <https://dancharblog.wordpress.com/2014/10/07/displayport-hdmi-dongles-activ…>

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slightly ot: trustworthy source for older mad hardware?
by Karen Lewellen 22 Nov '18

22 Nov '18

well, OSX is a UNIX based system I am told, so perhaps not totally off topic. Trustworthy source for slightly older Mac hardware? Meaning not on kigigi if that makes sense. I rather seriously seek a macbook or macbook pro old enough to still have line in line out and headphone jacks, and an optical drive. ideas? For example an apple users group, or someone hiding this in a closet? Cheers, Kare

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[GTALUG-Announce] GTALUG Meeting on Tuesday 11 December at 7:30pm
by hi＠gtalug.org 22 Nov '18

22 Nov '18

<https://gtalug.org/meeting/2018-12/> # VDO for CentOS, RHEL and beyond w/ Aaren deJong VDO is the new storage layer from Red Hat for block level compression, deduplication and zero-block omission. It's not just for RHEL and it's likely the start of something bigger for open-source storage. Those familiar with (open)ZFS might find this familiar and/or interesting. ## 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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[GTALUG-Announce] In The Community
by hi＠gtalug.org 14 Nov '18

14 Nov '18

# In The Community # November ## Toronto.js JS Workshop * Wednesday, 14th, 6:30pm * 1266 Queen St. West Suite #6 https://www.meetup.com/torontojs/events/bqlmqpyxpbrb/ ## Hacklab Toronto Junk Independence Day * Sunday, 18th 2pm - 7pm * 1266 Queen St. West Suite #6 * https://hacklab.to/archives/junk-independence-day-nov-18th/ ## Serverless Toronto Using Event Streams to orchestrate a Serverless Application * Tuesday, 20th, 6pm * Myplanet (Bank of Upper Canada Building), 252 Adelaide St. E. * https://www.meetup.com/Serverless-Toronto/events/254389273/ ## Toronto Perl Mongers * Thursday, 29th, 7pm * FlightNetwork, 145 King St West Suite 1400 * https://www.meetup.com/Toronto-Perl-Mongers/events/rhsxwpyxpbdc/ ## DEFCON Toronto (DC416) Exploring Hacked Data Services & Defending against the Magecart Gang * Thursday, 29th, 6pm * Bluecat, 4100 Yonge Street (3rd floor) * https://www.meetup.com/DEFCON416/events/256240821/ # December ## Polyhack Toronto * Wednesday, 5th, 7pm * H Bar, 859 Queen Street W * https://www.meetup.com/polyhackTO/events/255984757/ *** If you have an event to add to this monthly list, please contact: scott [at] gtalug [dot] org. --- GTALUG Announce mailing list announce(a)gtalug.org https://gtalug.org/mailman/listinfo/announce

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Dinner tonight?
by David Collier-Brown 13 Nov '18

13 Nov '18

What's the current state of thought??? https://wiki.gtalug.org/pre-meeting_dinner -- 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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[GTALUG-Announce] GTALUG Meeting Tonight
by hi＠gtalug.org 13 Nov '18

13 Nov '18

<https://gtalug.org/meeting/2018-11/> # Blockchain, the technology not the hype with Paul Mullins Let's take a look at what technologies were remixed and labelled blockchain and how blockchain has evolved since these ideas came together in Staoshi Nakamoto's Bitcoin white paper of 2008. ## 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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