./celery.sh 2 ⨯
You are using -A as an option of the worker sub-command:
celery worker -A celeryapp <...>
The support for this usage was removed in Celery 5.0. Instead you should use -A as a global option:
celery -A celeryapp worker <...>
Usage: celery worker [OPTIONS]
Try 'celery worker --help' for help.
Error: no such option: -A
As mentioned in the release notes (breaking changes) documentation:
The global options can no longer be positioned after the sub-command. Instead, they must be positioned as an option for the celery command
That means that you need to change from:
celery worker -A celeryapp <...>
to
celery -A celeryapp worker <...>
Is your first argument to Celery being the same as your file name?
app = Celery('tasks', broker='redis://localhost:6379/0')
I changed [tasks] same as my filename and run the command again, then it works.
celery -A myfilename worker