I'm also seeing issues with the GPG-keys in 2.9.3. I just did a fresh install from the iso found on
linuxcnc.org/downloads/
and the first command i ran was:
Code:
thomas@LinuxCNC-dev:~$ sudo apt update
Hit:1 http://deb.debian.org/debian bookworm InRelease
Hit:2 http://deb.debian.org/debian bookworm-updates InRelease
Hit:3 http://security.debian.org/debian-security bookworm-security InRelease
Hit:5 https://apt.packages.shiftkey.dev/ubuntu any InRelease
Get:6 http://download.opensuse.org/repositories/science:/EtherLab/Debian_12 ./ InRelease [1,575 B]
Hit:4 https://repository.qtpyvcp.com/apt develop InRelease
Err:6 http://download.opensuse.org/repositories/science:/EtherLab/Debian_12 ./ InRelease
The following signatures were invalid: EXPKEYSIG A94819A7CB97A204 science:EtherLab OBS Project <science:EtherLab@build.opensuse.org>
Hit:7 https://www.linuxcnc.org bookworm InRelease
Fetched 1,575 B in 1s (1,952 B/s)
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
146 packages can be upgraded. Run 'apt list --upgradable' to see them.
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://download.opensuse.org>
W: Failed to fetch http://download.opensuse.org/repositories/science:/EtherLab/Debian_12/./InRelease The following signatures were invalid: EXPKEYSIG A94819A7CB97A204 >
W: Some index files failed to download. They have been ignored, or old ones used instead.
...not sure why it isn't working...
I'm but no means a Linux guru, so my attempt to fix this was to try to jumble together a solution from this thread. I ended up fetching a new key:
Code:
KEYRING=/usr/share/keyrings/ethercat.gpg && curl -fsSL https://download.opensuse.org/repositories/science:/EtherLab/Debian_12/Release.key | gpg --dearmor | sudo tee "$KEYRING" >/dev/null
...but that didn't work, so i ended up deleting the old keys and copying the new one into their place:
Code:
sudo rm /etc/apt/trusted.gpg.d/science_EtherLab.gpg.key.*
sudo cp /usr/share/keyrings/ethercat.gpg /etc/apt/trusted.gpg.d/science_EtherLab.gpg.key.binary.gpg
sudo cp /usr/share/keyrings/ethercat.gpg /etc/apt/trusted.gpg.d/science_EtherLab.gpg.key.chroot.gpg
...i'm pretty sure this isn't the correct way to fix it, but now i can run apt update without errors. Maybe it can help someone else. I believe this is a bug in 2.9.3, since it was a completely fresh install(with available internet connection) and it was literaly the first command i ran and it failed...
Thanks! 
