December 2019 - 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.

3 9

Rust intro tonight (free)
by D. Hugh Redelmeier 03 Jan '20

03 Jan '20

I don't know anything about General Assembly but they are hosting a "Practical Introduction to Rust" at 18:30 Thursday (today). You need to register. <https://generalassemb.ly/education/practical-introduction-to-rust/toronto/9…> It is given by a Blad Filippov of Mozilla Preparation: "Bring a laptop with a code editor installed. Bonus points for installing the Rust toolchain: https://rustup.rs/" I'm going to go. I assume that the text editor I use qualifies as a code editor.

6 13

10TB drive seen as a 2TB drive (twice?)
by Evan Leibovitch 30 Dec '19

30 Dec '19

It's not an Xmas present as it was bought a few weeks ago, but I'm trying to install a 10TB WD (Red Pro) disk and it's not exactly going to plan. My original plan was to put the disk into an external case, plug it in to format and copy over files, then install it in the case. The system already has an SSD as /dec/sda, and two disks one of 3TB and the other of 4TB, all working fine. When I attach the external drive, lsblock and fdisk -l both report TWO new drives, /dev/sdd and /dev/sde, both of 2TB size. I went into set the disk from DOS to GPT but the size didn't change; Now fdisk -l reports: Disk /dev/sdd: 2 TiB, 2199023255040 bytes, 4294967295 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: gpt Disk identifier: 49FDD63D-6C95-46F0-B7B1-650038D8FB9B Disk /dev/sde: 2 TiB, 2199023255040 bytes, 4294967295 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes And cat /proc/scsi/scsi reports: Host: scsi10 Channel: 00 Id: 00 Lun: 00 Vendor: WDC WD10 Model: 1KFBX-68R56N0 Rev: 0200 Type: Direct-Access ANSI SCSI revision: 04 Host: scsi10 Channel: 00 Id: 00 Lun: 01 Vendor: WDC WD10 Model: 1KFBX-68R56NLUN1 Rev: 0200 Type: Direct-Access ANSI SCSI revision: 04 The disk model is WD101KFBX and its specs can be found here. <https://documents.westerndigital.com/content/dam/doc-library/en_us/assets/p…> All of the online guides I've consulted say that the full capacity of the drive should be visible once I switch it to GPT mode. Is this a USB limitation? Or is there something else I need to change? I've attached the output of hwinfo if that's any help. Thanks for any suggestions! -- Evan Leibovitch, Toronto Canada @evanleibovitch or @el56

7 15

Stream URL question
by Peter King 30 Dec '19

30 Dec '19

A few weeks ago, JazzFM changed ... something ... and I was no longer able to access the live stream at https://ice66.securenetsystems.net/CJRT. Now I get an "error -34 [HTTP:401 Unauthorized]" message. But if I navigate to that webpage, I get a player that I can click on without any credentials, and it plays just find. Since I use Streamripper 1.64.6 under Arch Linux for time-shifting some of their programming, this is not a workable solution. Anyone know the address of the live stream I can use now? Google hasn't been any help. Thanks. -- Peter King peter.king(a)utoronto.ca Department of Philosophy 170 St. George Street #521 The University of Toronto (416)-946-3170 ofc Toronto, ON M5R 2M8 CANADA http://individual.utoronto.ca/pking/ ========================================================================= GPG keyID 0x7587EC42 (2B14 A355 46BC 2A16 D0BC 36F5 1FE6 D32A 7587 EC42) gpg --keyserver pgp.mit.edu --recv-keys 7587EC42

4 5

DNS-over-HTTPS - what's the use?
by Giles Orr 24 Dec '19

24 Dec '19

Firefox now makes available DNS-over-HTTPS. I'm a big fan of security and privacy, but I'm struggling to see the gains here: we stop some hypothetical observer from finding out what domain name we're querying ... and then immediately turn around and ask that domain for a web page. You hid the destination in your first query ... only to immediately expose it with your next query. I admit I'm thinking of our hypothetical advisor being at the ISP: they'll see both types of queries anyway. I suppose the argument can be made that an observer on the path to the DNS but not at the ISP has been stymied, but this seems ... lower value. Still, is that primarily what this will stop? -- Giles https://www.gilesorr.com/ gilesorr(a)gmail.com

7 13

LLVM talk slides
by Christopher Browne 22 Dec '19

22 Dec '19

I have put the slides that we weren't able to see at the December meeting up on GitLab at the following link... https://gitlab.com/gtalug/board-meetings/blob/master/uploads/Introduction%2… It's possible Alex may shift that to a better place, but that should at least make them accessible. -- When confronted by a difficult problem, solve it by reducing it to the question, "How would the Lone Ranger handle this?"

2 1

Phishing is no mirage...
by Christopher Browne 19 Dec '19

19 Dec '19

This morning, I received a realistic looking message appearing to be from our hosting provider (linode) which was trying to convince me to send out my credit card information. Titled... "Linode Support Ticket 13142320 - Other - Account Limit reached. Please open a support ticket." This may even be more of a "spear phishing" thing as it it was broadly personalized to me, as I help manage the GTALUG account at linode. Something was looking suspicious about the URL... http://login.linode.com.login.return.to.https.21354545.paulinasfriends.com -- When confronted by a difficult problem, solve it by reducing it to the question, "How would the Lone Ranger handle this?"

12 30

Call for proposals for January 2020 lightning talks
by alex＠gtalug.org 17 Dec '19

17 Dec '19

Hello Everyone, We're planning to have lightning talks at our January 14, 2020 meeting. If you would like to give a lightning talk, please email speakers(a)gtalug.org. Event page -- https://gtalug.org/meeting/2020-01/ Gettogether event page -- https://gettogether.community/events/3158/lightning-talks/ and I will

1 0

another unique store gone: Above All Electronic Surplus
by Stewart C. Russell 17 Dec '19

17 Dec '19

Losing Active Surplus a few years back was bad, but this one seems worse: long-established electronic surplus/weird stuff/junk store Above All Electronic Surplus (635 Bloor W, at Euclid) is closed. I went by today and the windows were papered over and a For Lease sign was on the front. Steve, the owner, was inside tidying up, but the door was locked. Above All was where I went for the off-the-wall retro stuff I knew no-one else would carry. Appletalk cables? Bulk PC reset buttons (some still marked Turbo XT)? SCSI interfaces? Mac Classic RAM? These are all things I found at Above All. Above All has moved before. Let's hope this is the case again. cheers, Stewart

12 20

[GTALUG-Announce] Meeting on Tuesday, January 14 at 07:30 PM
by hi＠gtalug.org 16 Dec '19

16 Dec '19

<https://gtalug.org/meeting/2020-01/> # Lightning Talks with George Vari Engineering and Computing Centre, Room 203 _Lighting Talks_ 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. If you would like to give a talk during the meeting, all you have to do is write your name on a post-it and stick it on the whiteboard in the front of the room. When your talk gets selected, you will have five to present your idea, then five minutes of audience questions. ### Five Minute Talks ## 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

1 0