February 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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Build critique request and the story behind it.
by Russell 19 Apr '18

19 Apr '18

This year I purchased an APC UPS because of my flakey connection to the grid. Ominous read clicks coming from my boot drive cemented that decision. I am happy to say that not only did I avoid my biannual unexpected shutdowns, the UPS also sensed transient RF spikes. It begins to click, switching to the battery and back to mains, even though there is no visible disruption to service, although the emergency lighting in the hallway was triggered and beeped itself on. I decided to purchase a case and build a new desktop. I waited till now because I was loosely following Sarah Sharp, of Intel and listened to her comments on USB. Version 3.0 is RMA as of Jan this year and her general comment is that hardware development has peaked and so the immediate future is in developing software. Here is the case I chose. I take delivery tomorrow. http://www.coolermaster.com/case/lan-box-haf-series/haf-xb-evo/ Newegg has this combo on offer. Intel Core i5-7500 Kaby Lake 4-Core 3.4 GHz CPU w water cooling unit ASUS STRIX H270F GAMING MB G.SKILL 2 x 8G DDR4 As a creative anachronist or purposefull recycler, I haven't built a complete system from all new parts in a dozen years. I thought I'd get my hand in before arthritis takes over my hardware chops completely. I'd appreciate any warnings and caveats regarding this combo. I'm still window shopping but what I'm looking for is stability and longevity over gaming. This combo has DDR4 and USB 3.1. I'm kind of fixed on the usb but I'm not married to the ram. So suggestions which lower the cost are most appreciated. I have a 650w Corsair p/s which is ok but a big factor for me is the ambient noise and recommendations on a quiet supply would be appreciated. Noise is why I'm trying out water cooling. From the reviews on the case I'll probably have to replace the case fans, but who knows I might get lucky. I follow with interest the posts on UEFI, secure boot, SElinux, USB, udisks, udev, mobile linux and systemd. Now is my time to see if I have learned anything. Thanks to all posters. Regards -- Russell Sent by K-9 Mail

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PC build recommendation
by Alex Volkov 03 Apr '18

03 Apr '18

Hey everyone, I'm assembling a computer and I'm looking for some feedback. The computer I'm building I'll use for development, run some VMs, edit video time-to-time. I also already have a 1Gb hard drive which I plan to use for VMs. One of the big requirements is to be small size, lots of memory (eventually upgrade to 32GB) and have a somewhat beefy CPU (Thus Ryzen 2400G). I've chosen Asrock AB350 mini ITX because it's small and it's got dual HDMI. I'm thinking maybe I can reduce some specs to save a few bucks. Thanks, Alex. PCPartPicker part list: https://ca.pcpartpicker.com/list/Z6Rttg Price breakdown by merchant: https://ca.pcpartpicker.com/list/Z6Rttg/by_merchant/ CPU: AMD - Ryzen 5 2400G 3.6GHz Quad-Core Processor ($209.99 @ Memory Express) Motherboard: ASRock - AB350 Gaming-ITX/ac Mini ITX AM4 Motherboard ($142.75 @ Vuugo) Memory: G.Skill - Ripjaws V Series 16GB (1 x 16GB) DDR4-3200 Memory ($219.99 @ Newegg Canada) Storage: Crucial - MX300 275GB M.2-2280 Solid State Drive ($104.00 @ Mike's Computer Shop) Case: Antec - ISK 300-150 Mini ITX Desktop Case w/150W Power Supply ($96.99 @ PC-Canada) Total: $773.72 Prices include shipping, taxes, and discounts when available Generated by PCPartPicker 2018-02-26 19:26 EST-0500

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Re: [GTALUG] Linux Journal, RIP
by Stewart Russell 03 Mar '18

03 Mar '18

On Jan 31, 2018 18:01, "Tim Carroll via talk" <talk(a)gtalug.org> wrote: They are back. with new funding. linuxjournal2 http://www.linuxjournal.com/ I wish them good luck trying to refactor their way out of existing debt. Trying to claim they're brand-new, start-over but with a lead story about how the LJ crew are the same as in 1999 is not a good look. Stewart

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The current state of NFS
by Giles Orr 02 Mar '18

02 Mar '18

I used to use NFS back in 2000 - back when we still thought unsecured local services were okay. And I loved it - it was slow, but very useful. So I'd like to start using it again, but I want it secured. Apparently NFSv4 "mandates strong security" (according to Wikipedia): does that mean for authentication, or encryption of files "in flight," or both? And I keep seeing it mentioned with Kerberos: I've been researching Kerberos a bit and that really looks like something I'd rather NOT have to set up. Is it possible to run NFSv4 without Kerberos? Pointers to recent, good tutorials would also be deeply appreciated. I'm using Fedora 27 and Debian (stable or testing) on the clients. You can stomp me if you like for my plan to use a Raspberry Pi as the server - I'm not looking for speed as this will mostly be for backups. I'd probably use Raspbian unless there's a compelling reason to use one of the other Pi distros. Of course if this will really need more memory than the Pi has, that's another issue ... -- Giles https://www.gilesorr.com/ gilesorr(a)gmail.com

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[GTALUG-Announce] GTALUG Meeting on Tuesday 13 March at 7:30pm
by hi＠gtalug.org 01 Mar '18

01 Mar '18

<http://gtalug.org/meeting/2018-03/> # Round Table Q&A Session 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. ## Location George Vari Engineering and Computing Centre 245 Church Street, Room 203 Ryerson University <http://goo.gl/maps/16oJ2> <http://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: <http://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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Some hardware if anybody is interested.
by Alvin Starr 28 Feb '18

28 Feb '18

I have something like 25 Netapp 14 drive fiber channel disk enclosures RS-1401 populated with 15K 450G drives. There is also a NAF-0702 head and I also have a couple of Netapp NAF-0602s with 6 500G drives. They are free to a good home. If your interested contact me off list. -- Alvin Starr || land: (905)513-7688 Netvel Inc. || Cell: (416)806-0133 alvin(a)netvel.net ||

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Any Debian Developers here can help me sign my GPG key?
by tlugys.ats＠spamgourmet.com 26 Feb '18

26 Feb '18

Hi GTALUG members, Do we have any Debian Developers here? I am in the second step of becoming New Debian Maintainer process -- https://nm.debian.org/process/194 and now need to have my GPG key signed by a Debian member. I was directed to the THUG group (Toronto (GNU)/Hurd User Group) http://www.nongnu.org/thug/ but only to find that their listed email (thug(a)gnu.org) is no longer working. So I'm in a bad position now, and really hope that there is a Debian Developer here, or you know of, that can help me. I live in GTA, North York to be exactly. Any help can comfort my desperate heart. Thanks Antonio

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Unix and Linux System Administration Handbook 5th Ed. by Evi Nemeth et al
by Ivan Avery Frey 19 Feb '18

19 Feb '18

The fifth edition of this book was published on Aug, 8th of last year. There's an excellent short summary of systemd timers in section 4.9 and the foreword by Paul Vixie is wonderful. This book can be viewed for free with a valid library card. Navigate to elearning then Safari books. Ivan.

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Fedora Netinstall
by Howard Gibson 15 Feb '18

15 Feb '18

I have just upgraded my 32-bit laptop to Fedora 27. The install DVD is no longer available for 32-bit. I had to do a Netinstall. Netinstall is poorly documented, but the default settings all work, I was able to select the software I wanted, and it has all worked very well. I think I actually prefer Netinstall to the DVD. Has anyone else out there played with this? I have not yet updated my website notes. -- Howard Gibson hgibson(a)eol.ca jhowardgibson(a)gmail.com http://home.eol.ca/~hgibson

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