pubsub/Dead Letter Topic
Product: Cloud Pub/Sub
Step Type: AUTOMATED STEP
Description
This step checks if the subscription has a Dead Letter Topic attached. This is important to remove the messages that have failed processing out of the main subscription.
Failure Reason
No dead letter topic attached. [1]
[1] https://cloud.google.com/pubsub/docs/handling-failures#dead_letter_topic
Failure Remediation
Add dead letter topic to deliver to the topic any messages whose delivery retries has exceeded the threshold. Be aware that this is on best effort [1] and ensure the proper permissions are assigned [2]. Monitor dead-lettered message count[3] and pull from the subscription attached to the dead letter topic to investigate the message processing failures [4].
[1] https://cloud.google.com/pubsub/docs/handling-failures#how_dead_letter_topics_work [2] https://cloud.google.com/pubsub/docs/handling-failures#grant_forwarding_permissions [3] https://cloud.google.com/pubsub/docs/handling-failures#monitor_forwarded_messages [4] https://cloud.google.com/pubsub/docs/handling-failures#track-delivery-attempts