Does Azure Communication queue incoming SMS text messages? How many? For how long?
Maybe a better question is: Does Event Grid have message queing? Because i believe SMS sends events to the Event Grid.
Azure Communication Services SMS capabilities provide developers options to consume SMS received events. The events are posted to Azure Event Grid which provides out of the box integrations to process those using webhooks, Azure Functions, Power Automate / Logic App connectors, and more. https://learn.microsoft.com/en-us/azure/communication-services/quickstarts/sms/receive-sms?pivots=programming-language-javascript
It's recommended to subscribe to events with a Storage Queue. That suggests that events are not queued automatically, and you must roll your own.
if you’ve configured a dead letter for the subscription, it’ll be dropped over there (in a Storage container). Getting these dead letter events out of the Storage Account is a burden. Storage Queues are very cheap and have a very high uptime. When the Azure Function runtime isn’t running correctly for some reason, events aren’t lost but stored on the queue. https://www.serverlessnotes.com/docs/subscribe-to-queues-when-working-with-event-grid
