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war story: fixing a Fedora installation that got broken during update
by D. Hugh Redelmeier 21 Oct '24

21 Oct '24

Many people don't update their software. They claim that it only brings grief. I'm the opposite: I take any update offered in the hope it is an improvement. One of my computers hung during a Fedora update. I don't know why it happened because I wasn't there (I also don't watch paint drying). Symptom: booting would not get the the log-in screen (GDM?). Step 1: have booting log to the display Normally Fedora booting is quiet so as not to disturb the serenity of the user. In this case we want to see the log. It might tell us what's wrong and it might tell us how far it got before hanging. - at the GRUB boot menu, type "e" to be given the chance to edit the commands that GRUB will execute to boot Linux. - cursor to the end of the "linux" line - remove the last two parameters ("rhgb quiet") - type CTRL-x to get the modified commands executed Now lots of logging information will scroll by on the screen. In my particular case, it didn't tell me much but I could see that booting got a long way. Step 2: boot from a live Fedora USB and examine the system's HDD/SSD. I assume that you know how to boot from a live installation USB flash drive. It is easy from that desktop to examine the broken system. - SMART scanning the system's disk might by worthwhile, if only to eliminate that source of doubt. - file system checks are always a good idea In my particular case, I didn't see anything obvious. Complicated brain surgery can be done by starting up the broken system in a chroot environment. I started down that road but was interrupted before success or failure. Step 3: boot the system console mode, without a GUI. This had promise because it looked to me as if the failure was starting the graphical system Proceed like step 1, but after erasing "rhgb quiet", add " 3"; hit CTRL-X. Log in. Now you have a shell. Since the system failed after a software update, I decided to do more of them. You could instead back out of them. sudo dnf update Failure: There was a set of kernel packages that seemed to be half installed. I removed the half that was installed and asked again for an update. It worked. I could reboot the system and it would come up as expected. Success!

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Learning Go
by William Park 20 Oct '24

20 Oct '24

Dear Go experts, I finally decided to dive into Go. Searching around "go.dev", I can't seem to find proper introduction, suitable for C programmer. Can someone point me to where it might be buried? I want the usual introduction, starting with - data types, variables, data structures - syntax (Go seems to use more symbols than C) - if-then, loops, functions, etc. Eg. I started with func main() { code, text := fmt.Print ("Print:", "hello", "world\n") code, text := fmt.Printf ("Printf: %s %s\n", "hello", "world") code, text := fmt.Println ("Println:", "hello", "world") } and got errors. I managed to figure it out, by trial and error. Not very efficient learning...

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Linux and on line banking?
by Karen Lewellen 18 Oct '24

18 Oct '24

Hi folks, Anyone using Linux successfully to access their on line bank account? If so, where? TD is not a prospect, so may be opening another account where I can manage a few things this way, if inclusive of course. Happy fall, Karen

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October Meeting Reminder
by Alan Heighway 08 Oct '24

08 Oct '24

Calling All Gamers! Gaming on Linux Discussion <https://new.gtalug.org/?p=106> We’re going to have a discussion about gaming on Linux. Bring you questions, comments, concerns, and complaints about your experiences with Linux gaming. This will be a discussion, so participation is encouraged. We will be hosting this in person and online so there are no excuses for not joining us! See all the details below… Date / Time: October 8th, 2024 19:30 EST Location: In Person: TMU George Vari Engineering and Computing Centre, 245 Church Street (just north of Dundas), Room 201 (See note below) Online using Nextcloud: https://hub.gtalug.org/call/7m45sf9i NOTE: The doors to the building are normally locked. There will be someone from GTALUG at the doors on the southeast corner of Church and Gould to let people in. If you come late or don’t see anyone at the door please SMS at 647 657 6575 for THIS NIGHT ONLY. Do not call. *A*lan *H*eighway <http://heighway.ca/> heighway.ca VA3WAH / VA3YKZ [image: Please consider the environment before printing]

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cheap as dirt old notebooks
by D. Hugh Redelmeier 07 Oct '24

07 Oct '24

Dell Refurbished is an arm of Dell Canada that sells off-lease computers. They are having a sale right now: 25% off all systems with a coupon (shown on this page): <https://www.dellrefurbished.ca/hot-deals?cjdata=MXxOfDB8WXww&nocache=1&utm_…> Note: shipping is extra. The Dell Latitude 3310 looks a little tasty: <https://www.dellrefurbished.ca/item/dell-latitude-3310-no-os-000004/dell-la…> - $179 - 25% + shipping + tax (cheap as a Raspberry Pi 5 system) - OK CPU i5-8265U - Latitude line is a business line, so should be well made - only cosmetic grade B - no OS license. But we have Linux - I'm guessing that it has an open SoDIMM slot to add a second 8G, but I haven't checked - screen resolution is only 1366 x 768 - 100 day warrranty

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General Meeting Reminder
by Alan Heighway 30 Sep '24

30 Sep '24

Meeting our TMU Hosts with Dave Mason <https://new.gtalug.org/?p=91> Dave Mason, Chair of Computer Science at Toronto Metropolitan University, welcomes GTALUG back to our in-person meeting room. This will be our first meeting back since COVID, and much has changed (including the name of the University!) Date / Time: September 10th, 2024 19:30 EST Location: In Person: TMU George Vari Engineering and Computing Centre, 245 Church Street (just north of Dundas), Room 201 (See note below) Online using Nextcloud: https://hub.gtalug.org/call/7m45sf9i NOTE: The doors to the building are normally locked. There will be someone from GTALUG at the doors on the southeast corner of Church and Gould to let people in. If you come late or don’t see anyone at the door please SMS at 647 657 6575 for THIS NIGHT ONLY. Do not call. ------------------------------ Pre-meeting: Traditionally many GTALUG attendees have met for dinner at Kabul Express, 126 Dundas East, about an hour before the scheduled meeting. We will try this again on the 13th, but since the dining options in the area have expanded dramatically since we last met, we may decide on other locations for future meetings. *A*lan *H*eighway <http://heighway.ca/> heighway.ca VA3WAH / VA3YKZ [image: Please consider the environment before printing]

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Fedora 41 changes
by D. Hugh Redelmeier 30 Sep '24

30 Sep '24

Fedora Linux 41 should be coming out in about a month or so. The beta is already out. This page is a list of the changes relative to 40. I found it worth a glance. <https://fedoraproject.org/wiki/Releases/41/ChangeSet> Old habits die hard: I still use ifconfig(8) even though it is obsolete. It looks like it will be disappearing, along with the nework-scripts package.

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serious RCE vulnerability via CUPS
by D. Hugh Redelmeier 28 Sep '24

28 Sep '24

There is a serious vulnerability in CUPS. (As usual, it is over-hyped.) A single unsolicited UDP packet can get root access on your machine if you have cups-browserd running. But there are other vulnerabilitied in CUPS, as I understand it. There was a lot of arguing about how serious it is: serious or very serious? It was supposed to be embargoed but it leaked. <https://isc.sans.edu/diary/31302> <https://www.evilsocket.net/2024/09/26/Attacking-UNIX-systems-via-CUPS-Part-…> CUPS (the printing subsystem) is too promiscuous. And it runs as root. - no problem from the internet if you don't run CUPS (few servers and thus most things exposed to the internet). In particular, if a system is behind NAT, it is not exposed to attacks from the internet. - if your firewall blocks UDP port 631 (IPP), no problem behind it. - you should consider attacks from within your LAN. I wonder if a web page could use javascript to create a local attack. But if you want to print, update CUPS (fixes are out, I think). And some part are not fixed (cups-browserd in particular). I think that the simple act of printer discovery is no longer simple. (We just got a colour laser printer. I fed it the WiFi password. Now all our Linux computers can easily print to it. To use it with any Linux computer in the house, the only configuration was asking the print dialogue to use a different printer. I think cups-browserd enabled that.) (To be honest, I've never really thought network printers were trustable, just convenient. WiFi doubly so.) I don't know why anyone thought a big codebase like CUPS ought to run as root. Even after these fixes, the question remains. Michael Sweet, the/an original author of CUPS, left Apple, and has been working on a replacement. There are packages for my distro (Fedora) but I don't really know how it slides into the printing stack. <https://www.msweet.org/pappl/>

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Does anyone have experience with Tuxedo OS?
by Evan Leibovitch 27 Sep '24

27 Sep '24

Hi all. Does anyone here have any experience using Tuxedo OS? It appears to have three benefits over my current distro of choice, KDE Neon: - It's Snap-free by design; packages like Firefox that default as snaps come in Tuxedo from .deb respositories as god intended - It's current but not bleeding-edge KDE; I don't need the kind of aggressive rolling release that Neon does for the desktop while remaining conservative using Ubuntu LTS - It's already abandoned PulseAudio in favour of Pipewire; the version in Neon is broken and may be fixed when it upgrades to use Ubuntu 24.04, Any feedback is appreciated, especially regarding suitability in a dual-boot scenario. Thanks! -- Evan Leibovitch, Toronto Canada @evanleibovitch / @el56

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Programming/Consultancy job posting
by Jeffrey Pikul 17 Sep '24

17 Sep '24

Hello. I have a client who is running a home-brewed PHP 5.x web application on a MySQL database running on a Linux instance. Most of the work will be done on their site's cpanel interface on HostPapa, but there may be work to be done at their Queenston, New York location. This is consultancy work, not a full-time position. What they need is someone a lot better at PHP programming then I am, both to fix their current code issues and to migrate the system to a modern PHP version. The original programmer is long gone. There was an issue recently where php code failed when HostPapa "accidentally" upgraded the site up to php 7.2. This was solved by back-leveling to php 5.x, but the underlying issues remain, and now there are some slowdown issues. In the very short term, some sql statements inside of an ereg() verb will have to be rewritten to fix a problem with output grouping. I tried amending the existing SQL with a GROUP BY , and wasn't successful. When that is resolved, the existing ereg() and mysql_connect() statements will need replacement to something that exists in php 7.x and beyond. In the medium term, they would like a solution to work with this database capable of scanning incoming packages, updating the database directly, and printing to nearby label printers. In the longer term, migrating all of this to a proper virtual machine like Digital Ocean would be more stable, along with a look if there are any maintained FOSS systems that could provide a superior replacement. If interested, please contact me off-list at jpikul(a)rogers.com or jepikul(a)gmail.com Jeffrey Pikul jpikul(a)rogers.com jepikul(a)gmail.com

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