I am running Cloud Tasks using OIDC authentication to trigger a Cloud Function. While running ~40K queued tasks, I received a number of task failures (noticed by the fact that the Retries counter was incremented) and when I inspected the Previous Run they all said Status code 2 (UNKNOWN), Reason to retry UNKNOWN(2): HTTP status code 0. Additionally, on inspection of the logs, it does not appear that my Cloud Function was triggered. Upon retry of all these tasks, the Cloud Function was triggered and the task was processed successfully.
I am unsure of what this code means and how to respond to it. Are these just par for the course when using Cloud Tasks? Is this definitely not going to trigger my Cloud Function or could it potentially trigger it while also returning this status? Can I protect against this in any way? Am I paying for these failed dispatches?