Tag: Ack Deadlock
Deadlocks caused by unacknowledged messages or backpressure in JetStream acks.
| ID | Title | Description | Category | Technology | Tags |
|---|---|---|---|---|---|
| CRE-2025-0082 High Impact: 0/10 Mitigation: 8/10 | NATS JetStream HA failures: monitor goroutine, consumer stalls and unsynced replicas | Detects high-availability failures in NATS JetStream clusters due to: 1. **Monitor goroutine failure** — after node restarts, Raft group fails to elect a leader 2. **Consumer deadlock** — using DeliverPolicy=LastPerSubject + AckPolicy=Explicit with low MaxAckPending 3. **Unsynced replicas** — object store replication appears healthy but data is lost or inconsistent between nodes These issues lead to invisible data loss, stalled consumers, or stream unavailability. | Message Queue Problems | nats | NATSJetStreamRaftAck DeadlockUnsynced Replica |