By "boot disk," do you mean the main system (root or /
) partition or the /boot
partition? The former is your encrypted /dev/sda5
partition, but the latter is your unencrypted /dev/sda1
partition. (These identifications are assumptions based on sizes and how things are generally laid out in Ubuntu, but they're probably right.)
Your /boot
partition is 243MiB in size with 69MiB of that space going unused. The /boot
directory typically holds GRUB configuration files, Linux kernels, initial RAM disk (initrd) images, and a few other minor odds and ends. Your free 69MiB should be enough to hold a new kernel, but I've seen some other reports recently of people running into "insufficient disk space" messages when trying to upgrade with similar amounts of free space, so it could be your culprit. Try sudo apt-get autoremove
to remove your old kernels. For future reference, distributions that routinely create separate /boot
partitions generally make them on the order of 500MiB in size, so yours is a bit undersized by that standard. It should still be adequate, though, if managed properly.
Your encrypted (presumably root or /
) partition is almost 149GiB in size. That's more than enough for Ubuntu and just about any software you might reasonably install, so if it is the source of the error message, that suggests that user data is to blame. In this context, "user data" is pretty broad, and includes not only whatever you've stored yourself but also log files (stored in /var/log
), temporary files (in /tmp
), and others, depending on how the computer is being used. See here and here for a couple of questions and answers about locating where your disk space is being used. You'll need to boot into your regular installation or mount your encrypted partition in an emergency system to perform these analyses.