Azure Container Instance (ACI) offers a great way to run containers in Azure without requiring any underlying virtual machine infrastructure. It’s a serverless solution, where you only pay for the compute resources your containers use. In respect to AZ-204 (Developing Solutions for Microsoft Azure) examination, understanding how to run containers using ACI is essential.
Discovery of Azure Container Instances
Azure Container Instance (ACI) makes it easy to create and manage Docker containers in Azure, without having to provision virtual machines or adopt a higher-level service. Fundamentally, you can think of ACI as a way to run a container quickly and easily, without dealing with any of the underlying infrastructure.
- No infrastructure to manage: ACI is designed with developer productivity in mind, offering serverless containers. This means you don’t have to worry about patching, infrastructure maintenance, or capacity management.
- Fast startup times: ACI is particularly useful in situations where you need fast, on-demand container start-up.
- Flexible sizing: You can precisely tailor your usage to the exact amount of memory and number of CPUs your application needs.
- Ideal for microservices architectures, including batch jobs, bursty workloads, and jobs that do not require persistent storage.
Creating an Azure Container Instance
To deploy a container into Azure Container Instances (ACI), you define the container’s requirements in a file called a YAML file, and then deploy the container to Azure using the `az container create` command.
Here’s an example of a YAML file for a container that runs the public Microsoft ACI hello world image.
apiVersion: 2018-10-01
location: eastus
name: hello-world
properties:
containers:
– name: hello-world
properties:
image: mcr.microsoft.com/azuredocs/aci-helloworld
resources:
requests:
cpu: 1.0
memoryInGb: 1.5
osType: Linux
restartPolicy: Always
tags: null
type: Microsoft.ContainerInstance/containerGroups
Using the Azure CLI, you can deploy the YAML definition with the `az container create` command.
az container create –resource-group myResourceGroup –file hello-world.yaml
Observability and Diagnostics
Monitoring and diagnostics are crucial for any application to ensure its proper functioning and for the maintenance and optimization of its performance. Azure Monitor and its Log Analytics service provide deep insights into your application.
- Azure Monitor: It provides basic metrics such as CPU usage, memory usage, etc.
- Log Analytics: It helps to query, visualize and alert on the metrics and logs collected from your environment.
In conclusion, Azure Container Instance (ACI) is an excellent service for running containers in the Azure cloud. Whether you’re intending to use containers as part of your application architecture or for packaging and distributing your software, ACI provides an easy-to-use solution. The AZ-204 examination measures how well you can use containerized solutions, including ACI and understanding all the fundamental concepts surrounding it can ensure you successfully pass you AZ-204.
Practice Test
True or False: Azure Container Instances can execute outdated software.
- True
- False
Answer: False
Explanation: Azure Container Instances are recommended for running latest, up-to-date and secure package versions. They do not support outdated or insecure packages.
What is the service in Azure that offers a serverless way to deploy, run, and manage containers?
- a) Azure Container Registry
- b) Azure Container Service
- c) Azure Container Instances
- d) Azure Kubernetes Service
Answer: c) Azure Container Instances
Explanation: The Azure Container Instances provides an environment for running individual containers without requiring any underlying virtual machines.
True or False: Azure Container Instances are organized within resource groups.
- True
- False
Answer: True
Explanation: Like other Azure resources, you manage the lifecycle of ACI instances by placing them in resource groups.
Which one of the following can be used to deploy Azure Container Instances?
- a) Azure Resource Manager
- b) Azure CLI
- c) Azure portal
- d) All of the above
Answer: d) All of the above
Explanation: Azure Container Instances can be deployed using Azure Resource Manager Templates, Azure CLI, or the Azure portal.
True or False: Azure Container Instances serverless computing eliminates the need to manage infrastructure.
- True
- False
Answer: True
Explanation: Azure Container Instance is a managed service, meaning Azure handles all of the infrastructure management for you so you can focus on developing your applications.
Azure Container Instances support which of the following orchestration platforms?
- a) Kubernetes
- b) Docker Swarm
- c) Apache Mesos
- d) None of the above
Answer: a) Kubernetes
Explanation: Azure Container Instances support integration with Kubernetes through the virtual kubelet project.
True or False: Azure Container Instances are not suitable for long-running tasks.
- True
- False
Answer: False
Explanation: Azure Container Instances supports both short and long-running tasks.
Which language/s can be used with client libraries in Azure container instances?
- a) Python
- b) .NET (C#)
- c) Java
- d) All of the above
Answer: d) All of the above
Explanation: The Azure SDK supports languages like Python, .NET (C#), and Java for interacting with Azure resources, including the Azure Container Instances.
True or False: It is not possible to connect Azure Container Instances to Azure virtual networks.
- True
- False
Answer: False
Explanation: Azure Container Instances supports both public and virtual network connectivity.
Azure Container Instances are billed on a __________ basis.
- a) Per-hour
- b) Per-second
- c) Monthly
- d) Yearly
Answer: b) Per-second
Explanation: Azure Container Instances are billed on a per-second basis, you only pay for each second that an instance is running.
Interview Questions
What is Azure Container Instance?
Azure Container Instances (ACI) is a service that allows you to run containers directly on the Microsoft Azure public cloud, without provisioning any virtual machines or adopting any additional services.
Which container orchestrators integrates with Azure Container Instances?
Kubernetes, which is a container orchestrator platform, integrates with Azure Container Instances through the Virtual Kubelet project.
Can Azure Container Instances run both Linux and Windows containers?
Yes, Azure Container Instances supports both Linux and Windows containers.
What is the Azure Container Instance Connector for Kubernetes?
Azure Container Instance Connector for Kubernetes allows Kubernetes clusters to deploy to Azure Container Instances. It’s an implementation of the Kubernetes Virtual-Kubelet project.
How are Azure Container Instances billed?
Azure Container Instances are billed by the second, based on vCPU and memory usage.
Is there any limit to the number of containers you can run in an Azure Container Instance group?
An instance of Azure Container Instances can run a maximum of 60 containers in a container group.
How can you pull a private image into an Azure Container Instance?
To pull a private image into Azure Container Instances, you need to create a YAML file that includes the image registry credentials. Then, use the Azure CLI to create the container.
Can you deploy multi-container groups in Azure Container Instances?
Yes, you can deploy multi-container groups in Azure Container Instances. Each instance of a container in the group shares the same network, lifecycle, resources, and local storage.
How to expose an Azure Container Instances to the Internet?
To expose Azure Container Instances to the Internet, you can use an IP address, either public or private, and a DNS name label.
What is the role of a resource group in Azure Container Instances?
A resource group in Azure Container Instances is a logical collection of resources. It houses all the resources that are created in the Azure Container Instances.
How do you monitor Azure Container Instances?
Azure Monitor and Azure Log Analytics can be used to monitor Azure Container Instances.
Can an Azure Container Instance be restarted?
Yes, an Azure Container Instance can be restarted by using the az container restart command in the Azure CLI.
Can a persistent storage disk be attached to Azure Container Instances?
No, Azure Container Instances do not support attaching persistent storage disks. But Azure File shares can be used and mounted to provide persistent storage to the container.
Is Azure Container Instances a Platform as a Service (PaaS) offering?
Yes, Azure Container Instances is a PaaS offering that allows developers to upload their applications and run them in containers on the Azure cloud.
How are the software updates and patches managed in Azure Container Instances?
Azure handles the hardware, software, updates and patches, and typically all underlying infrastructure for the Azure Container Instances.