Exam AZ-104 topic 4 question 14 discussion

Answer is wrong. The correct Answer is A. First: in case you created on fault domain, you are limited with one update domain. You can test this. Second: By default, Azure uses 5 update domains and up to 3 fault domains. So, In case you created 10 vm in scale set. then you will have 2 vm in each update domain. So once one update domain is not available, then you get 4 domains with 8 vms as required.

Correct Answer: A VM Scale Set consists of a set of identically configured VMs. Availability Set consists of a set of discrete VMs. No more than 20% of the Scale Set upgrading at any time, then 2 machines out of 10 will have maintenance, the 8 remaining VMs will be up. Virtual machine scale sets are created with five fault domains by default in Azure regions with no zones. For the regions that support zonal deployment of virtual machine scale sets and this option is selected, the default value of the fault domain count is 1 for each of the zones. FD=1 in this case implies that the VM instances belonging to the scale set will be spread across many racks on a best effort basis. Reference: https://docs.microsoft.com/en-us/azure/virtual-machines/manage-availability https://docs.microsoft.com/en-us/learn/modules/build-app-with-scale-sets/2-features-benefits-virtual-machine-scale-sets https://docs.microsoft.com/en-us/azure/virtual-machine-scale-sets/virtual-machine-scale-sets-automatic-upgrade

To ensure that App1 always runs on at least eight virtual machines during planned Azure maintenance, you should create: A. one virtual machine scale set that has 10 virtual machine instances. A virtual machine scale set (VMSS) allows you to deploy and manage a set of identical virtual machines that can automatically scale up or down based on demand. By creating a VMSS with 10 virtual machine instances, you ensure that there are always at least eight instances available even during planned Azure maintenance events. With a VMSS, Azure handles the maintenance operations by automatically distributing the updates across the virtual machine instances, ensuring that a minimum number of instances are always available to serve your application. Therefore, the correct answer is A. one virtual machine scale set that has 10 virtual machine instances.

Confusing, but should be C. "By default, Azure will assign three fault domains and five update domains (which can be increased to a maximum of 20) to the Availability Set. When spreading your VMs over fault domains, your VMs sit over three different racks in the Azure data center. What is the default number of update domains for an availability set? five update domains. When you create an availability set, Azure creates five update domains by default. These update domains are spread across the fault domains in the availability set.

C is the answer Keyword here is "at least 8 VMs during Azure maintenance", it should be "Avail Set" and "Update Domain" VMs in differ update domain will not be reboot at the sametime. In that case, we need at least 9 update domain in order to ensure at least 8 VM always running, so C is satisfied

Exact same Q came in my exam on 30 April2023. My Ans A. as 20% goes at mainatnce if part of scaleset

VM have to be on different update domain

Answer is A.

Create scale set, put initial count 10 vm, A is right

Very Correct Answer: D If you have 3 default FDs and 12 VMs running, then if 1 FD is down, then 4 VMs are down, leaving you with at least 8 more running VM's at any given time. At any given time that a planned maintenance happens, you will always have at least 8 running VMs if 1 fault domain is down.

mlantonis has it right, it's A.

C is the one

Answer C

For those struggling with the near 50/50 split. I myself said, "C"; however, I'm comparing ExamTopics with Udemy and Udemy disagrees with the answer as well along with an explanation.

The correct Answer will be A (can be D if we are not looking on costs), tested it with the portal and when I set FD to 1 I could not change UD to anything than 1 and got this message shown on screenshit https://imgur.com/a/x0yyWlk

Correct answer: C This was actually one of the more interesting and intriguing question! It really makes you think. First: Both A and C solve problem of guaranteeing 8 VMs running. Not B: only one UD here, i.e. all could/will go down during planned host maintenance Not D: 12 VMs over 5 UDs, means two UDs will have 3 VMs each hence 7 VMs could end up running. So why C over A? Well first the question actually says "App1 will be hosted on several Azure virtual machines." This can be interpreted as several ("discrete") VMs, i.e. a VMAS and not VMSS which run the same VM in several instances. But mostly C over A due to the fact this scenario is about availability, i.e. creating redundant resources when things go down, and not scalability, i.e. creating redundant resources for performance reasons.

For Planned maintenance azure uses Update Domain, So C is correct answer