ended_at: 2022-08-18 18:44:29.313640
error: 'Migration 0021_migrate_to_bullseye gescheitert mit der Ausnahme /boot/ has
  less than 70MB available. This will probably trigger a crash during the upgrade
  because a new kernel needs to be installed. Please look for advice on the forum
  on how to remove old, unused kernels to free up some space in /boot/.: Abbruch'
interface: api
operation: tools_migrations_migrate_forward
parent: null
started_at: 2022-08-18 18:44:29.304384
success: false
yunohost_version: 4.4.2.8

============

2022-08-18 20:44:29,308: INFO - Durchführen der Migrationen 0021_migrate_to_bullseye...
2022-08-18 20:44:29,312: ERROR - Migration 0021_migrate_to_bullseye gescheitert mit der Ausnahme /boot/ has less than 70MB available. This will probably trigger a crash during the upgrade because a new kernel needs to be installed. Please look for advice on the forum on how to remove old, unused kernels to free up some space in /boot/.: Abbruch
Traceback (most recent call last):
  File "/usr/lib/moulinette/yunohost/tools.py", line 944, in tools_migrations_run
    migration.run()
  File "/usr/lib/moulinette/yunohost/data_migrations/0021_migrate_to_bullseye.py", line 80, in run
    self.check_assertions()
  File "/usr/lib/moulinette/yunohost/data_migrations/0021_migrate_to_bullseye.py", line 378, in check_assertions
    raise YunohostError("/boot/ has less than 70MB available. This will probably trigger a crash during the upgrade because a new kernel needs to be installed. Please look for advice on the forum on how to remove old, unused kernels to free up some space in /boot/.", raw_msg=True)
yunohost.utils.error.YunohostError: /boot/ has less than 70MB available. This will probably trigger a crash during the upgrade because a new kernel needs to be installed. Please look for advice on the forum on how to remove old, unused kernels to free up some space in /boot/.