April 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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Video of Evan's talk from the last meeting
by Alex Volkov 01 May '21

01 May '21

Hello everyone, The recording of the talk -- I've ditched my Linux desktops for Windows .... sorta with Evan Leibovitch Is available here -- https://youtu.be/HfranDwTZOU Alex.

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Fwd: Developer job postings at TPL
by Giles Orr 30 Apr '21

30 Apr '21

Toronto Public Library has posted three developer positions (and some other tech jobs!): https://www.torontopubliclibrary.ca/about-the-library/library-jobs/ You'll find them titled "ITS Senior Specialist (Web & Mobile Development)." I've heard the pay may not look competitive, but there are other benefits: a strong union means when we tell you you'll be working a 35 hour week, we mean it. Equally important, I really like our team. Feel free to mail me off list if you have questions (I only really know about the developer positions, the others are in another area). -- Giles https://www.gilesorr.com/ gilesorr(a)gmail.com

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OpenWRT 21.02 is on it's way!
by Scott Sullivan 28 Apr '21

28 Apr '21

Release Candidate 1 for OpenWRT 21.02 dropped last week. https://downloads.openwrt.org/releases/21.02.0-rc1/ Notable Features that mattered to me: * Kernel Upgrade, 4.14.221 => 5.4.111 * Availability of more 10G NIC drivers (bnx2x) * UEFI boot images for x86 targets * Raspberry Pi 4 support I recently have been working on building out some beefier firewalls for two sites with Fiber services. I needed something that could do wireguard without being terribly CPU bound. I also wanted to support greater then 1Gbps networking. I went with some used Dell SFF 3020 machines. i5-4570, 4G RAM, and two low profile PCIe slots (x16 & x1). Paired with some surplus BCM57840 cards and Intel 1G cards, these are turning into robust firewall boxs. -- Scott Sullivan

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Linus Torvalds Responds to Linux Banning University of Minnesota
by Aruna Hewapathirane 27 Apr '21

27 Apr '21

Hello Everybody, I am still trying to understand the reason 'why' would anyone even want to do this ? Here is some context: https://portswigger.net/daily-swig/ill-advised-research-on-linux-kernel-lan… And follow up from Linus himself: https://www.tomshardware.com/news/linus-torvalds-responds-to-linux-banning-… I am also thinking if these two guys actually managed to do this they should be part of the community responsible for linux security ? Or we just hang them high and pour honey all over them and set loose bees and wasps on them ? I am torn two ways. My heart says shoot them. My brain says hire them ? Sigh... Just thought everyone would want to know so sharing :-) Aruna

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Re: [GTALUG] Linus Torvalds Responds to Linux Banning University of Minnesota
by El Fontanero 26 Apr '21

26 Apr '21

On 2021-04-26 11:21 a.m., ac via talk wrote: > On Mon, 26 Apr 2021 10:03:50 -0400 > El Fontanero via talk <talk(a)gtalug.org> wrote: > <snip lotsa really cool stuff here> >>> How about something like a go-fund-me kind of service that >>> distributes the money to the successful contract killer? >>> I am sure something can be done over a blockchain. >>> If we could add in spammers I would be most happy. >> Absolutely nauseating. Shocking and horrifying. >> "Zero tolerance" means at the very least, that advocating murder is >> cause for immediate and permanent banning from this list, is it not? >> No, Toronto does not have the prevalence of firearms in the hands of >> people who casually say they want people shot or the people who >> casually agree with them, but our cousins to the south are an >> extremely important lesson that we do not want to emulate. >> > who said anything about firearms/guns? > > most contract killers I see on movies use poison, some have a stringy > type thingy where they hook it over the victims heads, others use a > knife (apparently killing is then more personal or enjoyable - go > figure, there are so many really and truly weird people out there...) > > I saw a movie the other day where the evil people placed the to be > killed victim in a box with spikes... YIKES!! > > and, anyway, as I understand the original post, it is intended as > humour, okay, well I guess you have to be weird like me to read is as > such? > > or is this thread now truly in the weeds? Weeds, no. FBI watchlist, yes. Thanks a lot. Now I have to keep all this email to try to prove that I'm not a member of a terrorist organization. That's it for me. I wish I had unsubscribed before the incitements to murder, but now it's too late. I leave you to yourselves.

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Re: [GTALUG] Linus Torvalds Responds to Linux Banning University of Minnesota
by Aruna Hewapathirane 26 Apr '21

26 Apr '21

On Sun, Apr 25, 2021 at 6:01 AM ac via talk <talk(a)gtalug.org> wrote: > > It is EVIL to represent yourself as something you are not. > Agreed and once again these are just 'my' layman thoughts on this. Misrepresentation I feel and think is forgivable ? We have all done it at some point on our lives ? Me without knowing I was actually doing so and was rather abruptly and suddenly made to realise this. I apologized, they accepted. No harm done, we moved on - together! But pre-meditated and strategically planned careful introduction of vulnerabilities into the kernel is most definitely not. So like I said before we find them and we shoot them. The community are justifiably pissed-off me being one. > > I am sure there are many who would like to see the operating system > which drives the Internet, FAIL on a desperate and massive scale. > There will always be such people. We need to work in unity and solidarity. And that work is based on trust. And when this trust is literally shot to hell well... we shoot them again ? > It is EVIL to knowingly sabotage open source in this manner. > Agreed 110% again. > > I hope and wish that ALL Opens Source Programmers BAN University of > Minnesota for LIFE. > Umm.. that is extreme ? Two people did this ? These two people do not make up the University ? And there have been earlier patches made in good faith that so far seem legit and vulnerability free ? Again if an academic institute is able to submit 'useful' patches that 'fix' real problems that should be welcome ? But then I understand no one will ever trust anything coming from Minnesiota ever again. > > I am sure that there are many Nation States or LARGE corporations that > has, in the past, infiltrated many open source projects in this same > fashion and I am sure that they are all EVIL for the damage and > destruction they cause to human freedom on a planetary scale. > > Deception, power, control and narcissistic. Hire these types of people? > > Hell No! > > Listen, do you remeber one of Linus's most famous quotes ? He said and I quote: "See, you not only have to be a good coder to create a system like Linux, you have to be a sneaky bastard too." So all I am saying is these two 'gentlemen' who introduced the vulnerabilities that can be exploited at a later time knew what they were doing so we can learn from them, document everything, analyse and ensure this does not have a wash-rinse-repeat pattern ? And we can always shoot them again after we find what we need to know ? Forgive me I did some digging and the reason was I really wanted to know 'where' this 'passion' was coming from. And what I find says you're from South Africa and the email came through Germany ? Hell GTALUG has people all over the planet ? Yikes.. > They, and their institution, are now known worldwide for being > ethically challenged. > You and me both want them dead but calmer minds ( like GregKH ) will prevail :-) In solidarity - Aruna > > On Sat, 24 Apr 2021 11:55:00 -0400 > Aruna Hewapathirane via talk <talk(a)gtalug.org> wrote: > > > Hello Everybody, > > > > I am still trying to understand the reason 'why' would anyone even > > want to do this ? > > > > Here is some context: > > > https://portswigger.net/daily-swig/ill-advised-research-on-linux-kernel-lan… > > > > And follow up from Linus himself: > > > https://www.tomshardware.com/news/linus-torvalds-responds-to-linux-banning-… > > > > I am also thinking if these two guys actually managed to do this they > > should be part of the community responsible for linux security ? Or > > we just hang them high and pour honey all over them and set loose > > bees and wasps on them ? > > > > I am torn two ways. My heart says shoot them. My brain says hire them > > ? Sigh... > > > > Just thought everyone would want to know so sharing :-) > > > > Aruna > > --- > Post to this mailing list talk(a)gtalug.org > Unsubscribe from this mailing list > https://gtalug.org/mailman/listinfo/talk >

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ot: headphone jac replacement?
by Karen Lewellen 23 Apr '21

23 Apr '21

I might add during the current lock down? Here is the scoop The primary device i use as my computer's speech synthesizer source has a 3.5 inch headphone jack, which has been getting looser over the past week or so. While I had hoped to find a way to tighten it before a disconnect, that hoped was dashed this afternoon. I do have the jac, in fact I have a spare, what I am wondering though is a couple of things. first, if I want to try, or must try reattaching this myself, which tool do I need? screwdriver, or wrench?..or something else? If I want it done by someone else, for which I would happily pay even if moving the machine might be a dance, where in Toronto might I take it in for the work? In theory it is rather important, the replacement synthesizer is s slight fire risk, as its casing is broken around the plug in area for its adapter. Also, it sounds like it has a could, which may become frustrating as I use my computer rather a great deal these days. Ideas? Thanks, Karen

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Follow-on from Evan's talk: WSLg (graphics!)
by Stewart C. Russell 22 Apr '21

22 Apr '21

I see that MS's WSL preview release that came out today now has graphics support via Wayland. It's got some clever stuff behind it, and is explained here: WSLg Architecture | Windows Command Line — https://devblogs.microsoft.com/commandline/wslg-architecture/ Accelerated graphics and a built-in Pulse Audio server. Rather nicely done. cheers, Stewart

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Docker, NodeJS and complexity
by William Witteman 22 Apr '21

22 Apr '21

I have some existing projects to contribute to that use NodeJS and Docker, and I am finding that getting set up to work on them is extremely daunting. I have never really used Docker. I have never really used NodeJS/npm/etc. I do know Javascript, but I don't build projects like this - it reminds me of Ruby-on-Rails, which I found to be a huge snarl of complexity. I know that the initial development was done on Macs, but in theory at least, I should be able to set up the Docker container and use that to get me into an equivalent development environment, but I don't really know how. Does anyone have a Debian-flavoured tutorial for setting up Docker/NodeJS so that I can build and run someone else's code? Thanks!

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