Ubuntu downloads upgrades as new kernel and leaves the old kernels in /boot so you have the option to revert to old kernels. This had my /boot on “low disk space” so I had to delete old kernels.
I followed the instructions in this thread for a fix.
- Check current version of your kernel with
- List down old packages with
dpkg -l 'linux-*' | sed '/^ii/!d;/'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d;s/^[^ ]* [^ ]* \([^ ]*\).*/\1/;/[0-9]/!d'
- Delete each package with
sudo apt-get -y purge some-kernel-package.