How to resolve the issue of Ubuntu system not being able to boot due to full disk?

If the Ubuntu system cannot boot due to a full disk, you can try the following solutions:

1. Access recovery mode: reboot the computer, press the Shift key at the Grub boot menu (if there is no Grub menu, try pressing the Esc key), and select recovery mode to enter.
2. Free up disk space: In recovery mode, select “Check all file systems” to check and repair file system errors. Then choose “Clean” to clear disk space.
3. Remove unnecessary files: Use command line tools to delete unnecessary files and directories such as temporary files, log files, and cache files. Clean up can be done using the following commands.
4. Please execute these commands in your terminal:
   – sudo apt-get autoclean
   – sudo apt-get autoremove
   – sudo apt-get clean
5. Increase disk capacity: If you are running out of disk space, you can consider expanding the disk capacity or deleting some large files to free up space. Tools like GParted can be used to adjust partition sizes.
6. Check the log files: Sometimes log files can become very large, you can use the following command to view and clean up log files:
7. Use the “du” command with sudo to check the total disk usage of the /var/log directory, then use sudo to delete the specified log file located in /var/log.
8. Move files to another disk: If there is an available disk, you can move some files to it to free up space.

If the above methods fail to solve the problem, it may be necessary to further examine other possible faults and repair or reinstall the system.