WARNING(2): "file_put_contents(): Only 0 of 6 bytes written, possibly out of free disk space"

WARNING(2): "mysqli_query(): (HY000/1030): Got error 28 from storage engine"

USER ERROR(256): "SQL Error"

Warning: Unknown: write failed: No space left on device (28) in Unknown on line 0

Warning: Unknown: Failed to write session data (files). Please verify that the current setting of session.save_path is correct (/app/Shopsystem/Dateien/cache/sessions/) in Unknown on line 0