Simple Message Queue (SMQ, formerly MNS) uses a dead-letter queue to store messages that are negatively acknowledged by consumers or for which all retries fail. This helps locate and process errors occur during the consumption of a message.
Dead-letter policy
Dead-letter status
If the maximum number of retries is reached, the message is dead-lettered and stored to the dead-letter queue.
The number varies depending on the retry policy. For more information, see Retry policy (NotifyStrategy).
Rules for saving dead-letter messages
When you create subscription, you can select a queue as the dead-letter queue to retain dead-lettered messages.
If the subscription type is a queue, do not use the queue as the dead-letter queue.
Create a dead-letter queue
Log on to the SMQ console.
In the left-side navigation pane, select .
On the Subscriptions page, click Create Subscription.
In the Create Subscription panel, activate the Enable Dead-letter , select a queue as the Dead-letter Queue, and click OK.
For other parameter configuration rules, see Subscription type.