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Securely wiping SSDs
by Giles Orr 29 Mar '24

29 Mar '24

I have, for many years, used "Darik's Boot and Nuke" on a USB stick to securely wipe spinning hard disks. It takes a long time, but I mostly understand and trust the process. I'm now at the point that I have to wipe and dispose of SSDs, and I'm feeling a bit shaky on the methodology. Here's what I did: # hdparm -I /dev/sdX Looked for enabled/locked/frozen in the output ... I won't go into making sure those are toggled correctly, but that appears to be needed. This also lists what appears to be info about doing a wipe on the drive: 6min for SECURITY ERASE UNIT, 60min for ENHANCED SECURITY ERASE UNIT Then, set a password (why? but seems to be needed): # hdparm --user-master u --security-set-pass foobar /dev/sdX Last, run the wipe: # hdparm --user-master u --security-erase-enhanced foobar /dev/sdX Doing something like `dd if=/dev/sdX bs=5M count=5 | strings` (or sending it to `less`) definitely shows that it's changed from something organized to something full of identical characters. But I've never seen this wipe process take more than 60 seconds, which makes me wonder about the `hdparm` declaration about the time required for a secure wipe. So I guess the big question is: should I trust this process? Do we really think it's securely wiped? Or should I be taking a hammer to the chips on the SSD because that's the only way to ensure it's fully wiped? -- Giles https://www.gilesorr.com/ gilesorr(a)gmail.com

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Re: [GTALUG] Debian Live Linux -- Change Overlay Filesystem -- From Tempfs Ramdisk To Hard Drive ?? [was] Re: Debian Live Linux -- Overlay Filesystem -- Where Allocated ??
by Steve Petrie 24 Mar '24

24 Mar '24

Thanks to Len Sorensen, Hugh Redelmeier and Ron(a)bclug.ca for taking their time offering suggestions, all of which I have investigated. * * * * * * Paranoia and low tolerance for anxiety have me deciding on this strategy, to get to a Debian 12 configuration with root filesystem persistence: (1) Buy a second multi-TB SATA hard drive to install in my Debian linux PC (Western Digital or Seagate). (1) Build a bootable live Debian 12.5 linux USB memory stick. (3) Use (2) to install Debian 12 on the new SATA drive, and use this SATA Debian 12 for ongoing regular daily operations. (3) Keep both the current bootable live Debian 11 USB memory stick, and the new bootable live Debian 12 linux USB memory stick, for emergency linux boot purposes. * * * * * * This strategy offers these benefits: (1) gets regular linux operations to most current Debian version, and simplifies life by booting directly from hard drive, (2) (hopefully) saves time by booting the PC from hard disk, instead of from USB memory stick, (3) adds a large comforting increment of hard disk capacity, complementing the current 1.8 TB hard drive, which already is almost 50% used, (4) leaves me with two (2) Debian emergency boot USB memory sticks. * * * * * * I will report back on results. Steve Petrie Etobicoke (Toronto), Ontario, Canada apetrie(a)aspetrie.net 416-233-6116

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Concert tickets for tonight, free
by Evan Leibovitch 22 Mar '24

22 Mar '24

Hi. I have a pair of tickets to a concert tonight (March 22) by musician Dan Hill, tonight at Hugh's Room (Broadview south of Gerrard). We're sick and can't go. If you're sure you can use them let me know in private email (not to the list). First response gets them. - Evan

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DOS > bash
by Ron / BCLUG 22 Mar '24

22 Mar '24

Okay, clickbait subject line, but hear me out. I had a bunch of files called *.sh for backing up stuff. I decided to use `run-parts` to run the entire folder of shell scripts at once. `run-parts` won't run *.sh files (?!?), they need to be *.s-h or something dumb. I wanted to REName *.sh -> *. In DOS: `ren *.sh *.` In bash, that will not work (with file globbing & pathname expansion enabled by default). I had to do this instead: for I in *.sh ; do mv ${I} ${I%%.sh} done Clearly, DOS > bash. (Told ya so, Hugh.) rb

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Solar eclipse
by William Park 21 Mar '24

21 Mar '24

Anyone planning a group trip for solar eclipse viewing? I guess I can go a little south (Niagara or along Lake Erie) and find a parking spot somewhere. But, we have had any group field day for long time. --

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Debian Live Linux -- Overlay Filesystem -- Where Allocated ??
by Steve Petrie 21 Mar '24

21 Mar '24

Greetings To The GTALUG Community: I'm trying to discover where an overlay filesystem is mapped, for a Debian live boot from a USB stick. After perusing a dog's breakfast of output from various linux commands, I am appealing to GTALUG members for guidance. * * * * * * I boot live Debian 11 linux from a USB memory stick. This provides an overlay filesystem: ... user@debian:~$ df -h Filesystem Size Used Avail Use% Mounted on udev 7.8G 0 7.8G 0% /dev tmpfs 1.6G 1.6M 1.6G 1% /run /dev/sdb1 3.5G 3.5G 0 100% /run/live/medium /dev/loop0 2.9G 2.9G 0 100% /run/live/rootfs/filesystem.squashfs tmpfs 7.8G 1.6G 6.3G 20% /run/live/overlay overlay 7.8G 1.6G 6.3G 20% / tmpfs 7.8G 0 7.8G 0% /dev/shm tmpfs 5.0M 4.0K 5.0M 1% /run/lock tmpfs 7.8G 8.0K 7.8G 1% /tmp tmpfs 1.6G 1.7M 1.6G 1% /run/user/1000 /dev/sdc1 59G 1.7G 57G 3% /media/user/245B-74A8 /dev/sda2 1.8T 767G 958G 45% /media/user/32ec11e8-082c-4ca5-b751-dc2852f9d5e2 user@debian:~$ ... * * * * * * I believe that the overlay filesystem provides the root directory for linux. Files under GNOME shows under Other Locations > Computer a root directory: ... user@debian:/$ ls -aAl total 0 lrwxrwxrwx 1 root root 7 Dec 17 2022 bin -> usr/bin drwxr-xr-x 2 root root 144 Dec 17 2022 boot drwxr-xr-x 18 root root 3580 Mar 20 17:58 dev drwxr-xr-x 1 root root 640 Mar 20 14:32 etc drwxr-xr-x 1 root root 60 Mar 20 08:14 home lrwxrwxrwx 1 root root 31 Dec 17 2022 initrd.img -> boot/initrd.img-5.10.0-20-amd64 lrwxrwxrwx 1 root root 31 Dec 17 2022 initrd.img.old -> boot/initrd.img-5.10.0-20-amd64 lrwxrwxrwx 1 root root 7 Dec 17 2022 lib -> usr/lib lrwxrwxrwx 1 root root 9 Dec 17 2022 lib32 -> usr/lib32 lrwxrwxrwx 1 root root 9 Dec 17 2022 lib64 -> usr/lib64 lrwxrwxrwx 1 root root 10 Dec 17 2022 libx32 -> usr/libx32 drwxr-xr-x 1 root root 60 Mar 20 08:17 media drwxr-xr-x 2 root root 3 Dec 17 2022 mnt drwxr-xr-x 2 root root 3 Dec 17 2022 opt dr-xr-xr-x 266 root root 0 Mar 20 08:14 proc drwx------ 1 root root 60 Dec 17 2022 root drwxr-xr-x 31 root root 800 Mar 20 08:17 run lrwxrwxrwx 1 root root 8 Dec 17 2022 sbin -> usr/sbin drwxr-xr-x 2 root root 3 Dec 17 2022 srv dr-xr-xr-x 13 root root 0 Mar 20 08:14 sys drwxrwxrwt 17 root root 400 Mar 20 18:49 tmp drwxr-xr-x 1 root root 80 Dec 17 2022 usr drwxr-xr-x 1 root root 140 Dec 17 2022 var lrwxrwxrwx 1 root root 28 Dec 17 2022 vmlinuz -> boot/vmlinuz-5.10.0-20-amd64 lrwxrwxrwx 1 root root 28 Dec 17 2022 vmlinuz.old -> boot/vmlinuz-5.10.0-20-amd64 user@debian:/$ ... When I right-click on the word Computer in the title bar of the Files window, and select Properties, it shows: ... Name / Type Folder (inode/directory) Contents 297,003 items, totaling 10.9 GB (some contents unreadable) The space allocation graphic shows: 1.7 GB used 6.7 GB available Filesystem type overlay Open in Disks ... * * * * * * I have tried using many linux commands to find out where the overlay filesystem is mapped: ... df -h ls -l /dev/disk/by-id gdisk (/dev/sda) gdisk (/dev/sdb) gdisk (/dev/sdc) cfdisk /dev/sda cfdisk /dev/sda cfdisk /dev/sdc sfdisk -J /dev/sda sfdisk -J /dev/sdb sfdisk -J /dev/sdc user@debian:/$ cd /dev user@debian:/dev$ ls -aAl sfdisk -T --label (dos, gpt) blkid lsblk lsblk parted -l mount sgdisk ... Output from all these commands is in the attached text file: ASP -- commands - looking for overlay filesystem device - 20240320.txt * * * * * * Suggestions from GTALUG members would be greatly appreciated !! Steve Petrie Etobicoke (Toronto), Ontario, Canada apetrie(a)aspetrie.net 416-233-6116

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Pi Day; Raspberry Pi virtual Meet-Up tonight
by D. Hugh Redelmeier 14 Mar '24

14 Mar '24

Pi Day (3.14) is no longer just a silly math undergrad joke. Even piza companies observe it. <https://en.wikipedia.org/wiki/Pi_Day> <https://www.todotoronto.com/posts/these-pizza-shops-are-offering-3-14-deals…> The Toronto Raspberry Pi meetup group is restarting tonight. <https://www.meetup.com/Raspberry-Pi/events/dhwnzrygcfbsb/> A new Raspberry Pi OS release is out.

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amazing but expensive Windows notebook (will run Linux)
by D. Hugh Redelmeier 12 Mar '24

12 Mar '24

Two left at the moment <https://forums.redflagdeals.com/ebay-canada-lenovo-15-off-coupon-2680997/#p…> The notebook: ThinkPad P16 with most nice features. The price ~$1400 + tax Too rich for me. But I can drool. Although this is sold through ebay, the vendor is Lenovo itself.

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uses and dangers of AI in science
by D. Hugh Redelmeier 12 Mar '24

12 Mar '24

I found this article quite interesting. <https://arstechnica.com/science/2024/03/producing-more-but-understanding-le…>

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Reminder: General Meeting- Tuesday, March 12
by Alan Heighway 11 Mar '24

11 Mar '24

The Future of LUGs and the Open Source Community. It’s AI, Baby! <https://gtalug.org/meeting/2024-03/> with Marcel Gagné <https://gtalug.org/> 12 March, 2024 at 07:30 PM Join GTALUG and our guest this month, Marcel Gagné, to discuss the current state of Linux User Groups and AI. We're going to use Big BLue Button for this meeting: https://blue.lpi.org/b/eva-zjc-gjy-kgl *Time:* March 12th, 2024 19:30 AM Eastern Time *Join us on Big Blue Button:* https://blue.lpi.org/b/eva-zjc-gjy-kgl. *A*lan *H*eighway <http://heighway.ca/> heighway.ca VA3WAH / VA3YKZ [image: Please consider the environment before printing]

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