AttributeError: 'DisabledBackend' object has no attribute '_restore_group'

[mahendrap1512]

Setup Details

1. celery version = 5.2.7
2. python version = 3.8.0
3. redis==4.5.4
4. celery backend = redis (managed service from AWS)
5. celery message broker = rabbitmq
6. REDIS_URL is the URL of redis service (properly set, checked by logging it)
7. BROKER_URL is rabbitmq url (also properly set)

Celery app instantiate

CELERY = Celery('celery_tasks',
                backend=REDIS_URL,
                broker=BROKER_URL)
celery_config = 'celery_config'
CELERY.config_from_object(celery_config)
CELERY.conf.CELERY_RESULT_BACKEND = REDIS_URL

Code

        jobs = chord(group(
            CELERY.signature('celery_task_1',
                             kwargs={<kwargs related to celery task 1>}).set(
                queue="queue1") for file in files),
            CELERY.signature('celery_task_2', immutable=True, kwargs={<kwargs related to task 2>}).set(
                queue="queue2"))
        result = jobs.apply_async()

This code is "intermittently" raising following error

raised: AttributeError("'DisabledBackend' object has no attribute '_restore_group'")
Traceback (most recent call last):
  File "/usr/local/lib/python3.8/dist-packages/celery/backends/redis.py", line 488, in on_chord_part_return
    header_result = GroupResult.restore(gid)
  File "/usr/local/lib/python3.8/dist-packages/celery/result.py", line 960, in restore
    return backend.restore_group(id)
  File "/usr/local/lib/python3.8/dist-packages/celery/backends/base.py", line 656, in restore_group
    meta = self.get_group_meta(group_id, cache=cache)
  File "/usr/local/lib/python3.8/dist-packages/celery/backends/base.py", line 649, in get_group_meta
    meta = self._restore_group(group_id)
AttributeError: 'DisabledBackend' object has no attribute '_restore_group'

I checked my backed service, Redis service is running properly without any issue, not sure why this error is raised randomly.
Any thoughts?

[50-Course]

hi @mahendrap1512, what's your redis version again?

[mahendrap1512]

Hi @50-Course
We are using managed redis service from AWS
And redis library version is "redis==4.5.4"