Exam AZ-304 topic 15 question 1 discussion

To me, the key points: -middle tiers of the payment processing system can increase or decrease automatically based on CPU utilization -Minimize the effort required to modify the middle-tier API  -The middle-tier and the web front end must continue to operate without any additional configurations All leading to A

A it fits the requirement: "Ensure that the number of compute nodes of the front-end and the middle tiers of the payment processing system can increase or decrease automatically based on CPU utilization."

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Requirements: 1. Host the middle tier of the payment processing system on a virtual machine 2. Autoscaling This leaves A as the only option to achieve the requirements

Correct Answer

"Ensure that the number of compute nodes of the front-end and the middle tiers of the payment processing system can increase or decrease automatically based on CPU utilization. Ensure that each tier of the payment processing system is subject to a Service Level Agreement (SLA) of 99.99 percent availabilty." https://azure.microsoft.com/en-us/support/legal/sla/summary/ Virtual Machine Scale Sets is a free service, therefore, it does not have a financially backed SLA itself. However, if the Virtual Machine Scale Sets includes Virtual Machines in at least 2 Fault Domains, the availability of the underlying Virtual Machines SLA applies https://azure.microsoft.com/en-us/support/legal/sla/virtual-machines/v1_9/ For all Virtual Machines that have two or more instances deployed across two or more Availability Zones in the same Azure region, we guarantee you will have Virtual Machine Connectivity to at least one instance at least 99.99% of the time. A is the answer

Answer - Availablity set Reasons - scale set has not SLA, it has SLA on underlying VM Availabllity set has SLA of 99.95 and Availavai;ity zone of 99.99%, so we need availability set in on 2 zone. Any inputs???

A is correct. Ensure that each tier of the payment processing system is subject to a Service Level Agreement (SLA) of 99.99 percent availabilty Infrastructure services must remain available if a region or a data center fails. Host the middle tier of the payment processing system on a virtual machine

Why not D: Function App?

''A'- Correct Answer

To protect your virtual machine scale sets from datacenter-level failures, you can create a scale set across Availability Zones. Azure regions that support Availability Zones have a minimum of three separate zones, each with their own independent power source, network, and cooling. For more information" https://docs.microsoft.com/en-us/azure/virtual-machine-scale-sets/virtual-machine-scale-sets-use-availability-zones

This would not be complient with the requierment "If a data center fails, ensure that the payment processing system remains available without any administrative intervention. The middle-tier and the web front end must continue to operate without any additional configurations."