Erwan David composed on 2022-10-01 16:21 (UTC+0200):
My /boot is 235 MB (from deb 10 installer), however in testing I now
have 56MB initramfs files and update-initramfs cannot work for the 3rd
kernel to install (and apt autoremove keeps 2 kernels, thus at upgrade
there are temporarily 3 kernels).
I see that all the files of the initramfs are put in /boot before
creating the compressed image, thus the need for place. Is there a way
to cofigure update-initrams so that the creation of the im age is done
in another filesystem before instalation in /boot ?
Alternative options:
1-Move the oldest kernel files to another filesystem, or everything, from /boot.
You don't need them there until time to reboot.
2-You're not forced to keep two kernels. Remove the non-running one manually.
3-As Stefan already suggested, MODULES=dep. It's routine here. Big initrds take
more time to load, which can be quite noticeable on old hardware.
4-Is your /boot adjacent to your swap? If yes, easily recreate both, with smaller
swap, larger /boot. Don't forget to adjust fstab for UUID change of swap, or apply
the one from fstab on the new.