Can’t rebuild system do to /boot being full

[Halbert]

My system can’t rebuild/update because my /boot has 0 available space. When trying to rebuild, I get

Failed to copy data from “/nix/store/wxyn8d3m8g4fnn6xazinjwhzhzdg6wib-systemd-259/lib/systemd/boot/efi/systemd-bootx64.efi” to “/boot/EFI/systemd/.#systemd-bootx64.efi36b647d9863a40fe”: No space left on device
Failed to copy data from “/nix/store/wxyn8d3m8g4fnn6xazinjwhzhzdg6wib-systemd-259/lib/systemd/boot/efi/systemd-bootx64.efi” to “/boot/EFI/BOOT/.#BOOTX64.EFI11be8dd88240bbc0”: No space left on device

I tried doing sudo nix-collect-garbage --delete-old and then rebuilding but that didn’t work either. Doing a rebuild boot also doesn’t work.

nixos-rebuild list-generations show generation 244 build today whereas the boot menu shows the latest generation to be 213 built on 2025-02-08. I know it can’t be this newer generation I’m on as none of my packages have updated over the past month.

I’m currently on the unstable 26.05 release.

[waffle8946]

(NixOS) (FIXED) Can't nixos-rebuild switch because /boot is full even after nix-collect-garbage -d

Delete the old kernels manually from /boot (I’d keep at least one old one). Then delete those previous generations (I’d keep 1-2). Then rebuild. Yeah it’s annoying. I keep my /boot at least 500 MiB for this reason.

Failed to install bootloader warning: error(s) occurred while switching to the new configuration

I was not intending to be that haphazard. In /boot/EFI/nixos/ you will see kernels and initrds. I manually delete the older versions in that directory, then delete some old NixOS generations + gc using sudo nix-collect-garbage --delete-older-than <whatever>, then sudo nixos-rebuild boot.