त्रुटी आणि पुनः प्रयत्न हाताळणे विश्वसनीय RabbitMQ उपभोक्त्यांसाठी महत्वाचे आहे — जेव्हा संदेश प्रक्रिया अयोग्य होते तेव्हा काय करायचे हे ठरवणे (पुनः प्रयत्न, dead-letter, किंवा टाकून देणे). योग्य त्रुटी हाताळणी संदेश गमावणे आणि अडकलेले उपभोक्ते रोखते.
समस्या
When a consumer fails to process a message (bad data, downstream failure, bug):
→ requeue forever → a "poison" message blocks the queue (retried endlessly)
→ discard → message LOST
→ crash → reprocess, possibly stuck again
→ need a deliberate strategy.
पुनः प्रयत्न धोरणे
✓ NACK + REQUEUE → reject and requeue for retry (but limit retries — don't requeue forever)
✓ RETRY WITH BACKOFF → retry transient failures with increasing delays (e.g. via a delayed
retry queue with TTL → requeue after a delay)
✓ RETRY LIMIT → track attempts; after N failures → DEAD LETTER (don't retry forever)
✓ Distinguish TRANSIENT (retry) vs PERMANENT (dead-letter immediately) failures
