Unable to to scan without `sudo`

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1

I’m trying to set up scanning on my 24.11 NixOS and it doesn’t work.

I’m following the docs. Basically, everything down to enabling the avahi services. The printer isn’t found, though I have added my user to the scanner and lp groups.

It (→ scanimage -L) does, however, work with sudo, which indicates to me that this is not a driver, network, or any other problem but comes down to permissions. Unfortunately, I have no idea what permissions, as I think I followed all the instructions. So that article may need updating. Did anybody get this to work?

Not sure how much it matters, but the printer/scanner in question is a Canon Pixma MG 3550.

2

Those are not “docs” (the only official documentation are the option descriptions for this module), and it’s also not the correct wiki, but the unmaintained one hogging page rankings for historic reasons. This is the official wiki: Scanners - NixOS Wiki

Have you rebooted/relogged since adding yourself to the groups? Group changes don’t immediately take effect in existing sessions.

3

Thanks for pointing out that I was using the wrong wiki. However, there don’t seem to be any relevant differences in the current one. And yes, I logged out, added the groups imperatively, rebooted, all that. Still, only works as root

4

Do you get any logs if you run sudo journalctl -f in a separate terminal before scanning as your user?

5

Hi, permissions for printers are setup with udev rules. Details are given in this issue, it’s not simple so I’d rather not repeat them here