Exam AZ-204 topic 1 question 7 discussion

Answer is B 20 Each availability set can be configured with up to three fault domains and twenty update domains. https://docs.microsoft.com/en-us/azure/virtual-machines/availability-set-overview

Should be 20

In Azure, an availability set can be configured with up to 20 update domains. Setting the platformUpdateDomainCount property to 20 ensures that your virtual machines are distributed across the maximum number of update domains, which helps maintain accessibility during fabric failures or maintenance.

"Update domains indicate groups of virtual machines and underlying physical hardware that can be rebooted at the same time. When more than five virtual machines are configured within a single availability set with five update domains, the sixth virtual machine is placed into the same update domain as the first virtual machine, the seventh in the same update domain as the second virtual machine, and so on." Given that we want to maximize the number of VMs available at all times, we want to maximize the number of update domains – e.g. a single update domain would basically mean no redundancy at all. Having said that, there is a constraint on the maximum number of update domains: "Each availability set can be configured with up to three fault domains and twenty update domains." Source: https://docs.microsoft.com/en-us/azure/virtual-machines/availability-set-overview#how-do-availability-sets-work

So I know the answer is B for sure, but still trying to wrap my head around the relationship between fault domain, update domain, and availability sets. Someone, please correct me, but from my understanding. Let's say I add 60 virtual machines to an availability set. Azure would distribute the VM across the 20 domain update domains, with each update domain containing three virtual machines. These Fault Domains can hold multiple Update Domain Groups. For Example, Fault Domain 1 could hold Update Domain Group 1 - 6. So if I were to do maintenance to Update domain 1, my clients would still have available for update domains 2 - 6. However, if Fault Domain 1 Goes down, then all Update Domains 1 -6 will also go down. https://learn.microsoft.com/bs-latn-ba/azure/virtual-machines/availability-set-overview#how-do-availability-sets-work

The correct answer is B. 20. The platformUpdateDomainCount property in Azure Resource Manager (ARM) templates specifies the number of update domains that should be created for the availability set. The maximum value for this property is 20. By configuring the platformUpdateDomainCount property to the maximum value, you can help to ensure that your virtual machines are distributed across as many update domains as possible, which will help to protect them from maintenance operations that require updating virtual machines in a single update domain.

The `platformUpdateDomainCount` property in an Azure Resource Manager (ARM) template specifies the number of update domains for the Azure virtual machines within an availability set. Update domains are groups of VMs that are updated and rebooted together during planned maintenance events to minimize downtime for applications. The maximum value allowed for `platformUpdateDomainCount` is 20. Therefore, to ensure that the ARM template allows for as many virtual machines as possible to remain accessible in the event of fabric failure or maintenance, you should configure: B. 20

Each virtual machine in your availability set is assigned an update domain and a fault domain by the underlying Azure platform. Each availability set can be configured with up to 3 fault domains and 20 update domains.

B is correct

The maximum value you can configure for platformUpdateDomainCount is 20. This means that virtual machines within the availability set will be spread across 20 update domains. By setting this value to the maximum, you ensure that the virtual machines are distributed optimally for availability during maintenance or update operations.

Answer is B 20

The upper limit of platformUpdateDomainCount is 20

https://learn.microsoft.com/en-us/azure/virtual-machines/availability-set-overview

B 20 is the correct one.

A higher value would generally be preferable to improve availability. Among the options, D. 40 would provide the highest degree of isolation and availability during maintenance or updates. Therefore, you should configure the platformUpdateDomainCount property with a value of 40

A higher value would generally be preferable to improve availability. Among the options, D. 40 would provide the highest degree of isolation and availability during maintenance or updates. Therefore, you should configure the platformUpdateDomainCount property with a value of 40

To ensure high availability within an Azure availability set, you need to distribute virtual machines across different update domains and fault domains. Update domains represent groups of virtual machines that can undergo maintenance or updates together, minimizing potential downtime. For the best balance between high availability and maintenance, it's recommended to set the platformUpdateDomainCount property to 20. This ensures that your virtual machines are spread across 20 update domains. The platform imposes a default limit of 20 update domains in each availability set.