ACI is a serverless container engine that can be used when you want to run your containers for a limited amount of time during the day, when you need fast provisioning but don't need advanced orchestration capabilities, or when you need to handle peaks in your AKS infrastructure (using virtual nodes).
ACI provides all the scheduling and managing capabilities of a traditional orchestrator, but it's optimized to handle a single container, not a set of containers. You can run as many containers as you need, but each of them is independent of the others. With ACI, you don't need to think about the underlying VM infrastructure since all the resources are managed by Azure and are fully transparent.
With ACI, you only pay for the amount of time that your container is running, and you don't need to set up any infrastructure.
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