Exam AZ-400 topic 8 question 11 discussion

Should be C It requires self-hosted agent rather than Microsoft-hosted agent. It is better to use scale set according to the following link https://docs.microsoft.com/en-us/azure/devops/pipelines/agents/agents?view=azure-devops&tabs=browser Azure virtual machine scale set agents Azure virtual machine scale set agents are a form of self-hosted agents that can be auto-scaled to meet your demands. This elasticity reduces your need to run dedicated agents all the time. Unlike Microsoft-hosted agents, you have flexibility over the size and the image of machines on which agents run. You specify a virtual machine scale set, a number of agents to keep on standby, a maximum number of virtual machines in the scale set, and Azure Pipelines manages the scaling of your agents for you. For more information, see Azure virtual machine scale set agents.

B. Azure Container Instances - this will be less on price

The solution must minimize costs.

Correct answer С Based on the most recent Microsoft documentation, the recommended compute type for the self-hosted agent in your Azure Pipelines build pipeline is: C. an Azure virtual machine scale set Explanation: Azure Virtual Machine Scale Sets (VMSS): This option is cost-effective for scenarios where you need to run build pipelines periodically and want to manage the scale of your virtual machines efficiently. VMSS allows you to automatically scale the number of VMs based on demand and set the number of VMs to zero when not in use, which helps minimize costs.

C - requires a self hosted agent

B. Azure Container Instances Explanation: Cost Efficiency: Azure Container Instances (ACI) are billed per second based on the resources you allocate to your container, making it a very cost-effective solution for workloads that run infrequently or for short durations. Ease of Use: ACI is straightforward to set up and tear down, which suits a build pipeline running once daily for a short duration. Scalability: While not as scalable as Kubernetes or VM scale sets for high-demand scenarios, ACI is perfect for intermittent and short-lived tasks, such as a daily build process. Options A, C, and D generally involve higher ongoing costs due to their more persistent nature and additional management overhead:

C with number of standby agents set to 0 there will only be an agent spon up when there is a job. https://learn.microsoft.com/en-us/azure/devops/pipelines/agents/scale-set-agents?view=azure-devops

Scale set allows you to configure the scale set agent pool to have zero agents on standby. if you set Number of agents to keep on standby to zero, for example to conserve cost for a low volume of jobs, Azure Pipelines starts a VM only when it has a job. Reference: https://learn.microsoft.com/en-us/azure/devops/pipelines/agents/scale-set-agents?view=azure-devops#can-i-configure-the-scale-set-agent-pool-to-have-zero-agents-on-standby

Container Instance

Final answer after going through all the comments Azure Container Instances

If the primary concern is cost minimization, then Azure Container Instances (ACI) can indeed be more cost-effective than Azure Virtual Machines for short-lived tasks or infrequent operations. Azure Container Instances bills per second, and for a task that runs for 30 minutes once a day, ACI might be a better financial choice. The advantage of ACI is that you only pay for the actual compute resources you consume, without any VM infrastructure overhead.

ChatGPT: For a build pipeline that runs once daily and takes 30 minutes to complete, I would recommend using Azure Container Instances to minimize costs. Azure Container Instances is a service that allows you to run containers directly, without the need for any virtual machine infrastructure. This makes it a cost-effective option for workloads that have short running times and do not require persistent storage, such as a build pipeline that runs once daily for 30 minutes. On the other hand, an Azure virtual machine scale set is designed to provide easy management of multiple virtual machines and automatic scaling of resources, which may not be necessary for this particular use case1. So, the best option would be B. Azure Container Instances.

You are asked for the cheapest, not the fastest, considering this will run for half an hour a day, B - ACI is the correct answer.

For this scenario, where the build pipeline requires a self-hosted agent and needs to run once daily for a period of 30 minutes, the most cost-effective compute type to recommend would be an Azure virtual machine. Azure virtual machines (VMs) can be created and configured with the required build tools and dependencies, and can be used as self-hosted agents for Azure Pipelines. They offer the flexibility to choose the appropriate size and configuration based on the workload requirements. Additionally, they can be started and stopped on-demand to save costs when not in use. Azure Kubernetes Service (AKS) cluster and Azure Container Instances (ACI) are container-based compute options, which are more suitable for running long-running, highly-scalable applications. They may not be the most cost-effective option for this scenario. An Azure virtual machine scale set (VMSS) can automatically scale up or down based on the workload demand, but it may be overkill for a build pipeline that runs only once daily.

AI has another option: Azure virtual machines would be the most cost-effective option for running a self-hosted agent for a daily 30-minute build pipeline. Virtual machines can be started and stopped as needed, allowing you to only pay for the compute resources you actually use. Additionally, virtual machine scale sets can automatically scale the number of agents based on demand, further optimizing costs. AKS and Azure Container Instances may be more appropriate for containerized workloads or applications that require high scalability, but for a simple daily build pipeline, virtual machines would be the best option.

https://docs.microsoft.com/en-us/azure/devops/pipelines/agents/docker?view=azure-devops "minimize costs" so all the more answer is B

Azure Pipelines scales in the agents when the number of idle agents exceeds the standby count for more than 30 minutes (configurable using Delay in minutes before deleting excess idle agents). https://docs.microsoft.com/en-us/azure/devops/pipelines/agents/scale-set-agents?view=azure-devops#how-azure-pipelines-manages-the-scale-set