Azure VM SLA for 99.99% Availability
Answer
Correct answer: B — The solution does not meet the goal because achieving 99.99% availability requires at least two virtual machine instances deployed across two availability zones.
Note: The question is included in a number of questions that depicts the identical set-up. However, every question has a distinctive result. Establish if the solution satisfies the requirements. You are tasked with deploying a critical LOB application, which will be installed on a virtual machine, to Azure. You are informed that the application deployment strategy should allow for a guaranteed availability of 99.99 percent. You need to make sure that the strategy requires as little virtual machines and availability zones as possible. Solution: You include one virtual machine and two availability zones in your strategy. Does the solution meet the goal?
Community Insight
The question tests the specific Azure SLA thresholds for Virtual Machines, where 99.99% is strictly tied to multi-instance deployments across multiple zones.
Achieving a 99.99% availability SLA for Azure Virtual Machines requires deploying two or more instances across two or more Availability Zones. A single VM cannot meet this guarantee regardless of zone configuration.
Learners often assume that including availability zones in the strategy is sufficient, failing to realize that a single virtual machine instance cannot be distributed across multiple zones simultaneously.
Community Discussion (30 comments)
Said Ismail
👍 1
Selected: B
A single VM cannot be distributed across two availability zones.
eduardok95
👍 1
Selected: B
nooo. at least 2 vms
Pefl
👍 1
Selected: A
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.
AlekksMaciel
👍 1
Selected: A
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.
Rcosmos
👍 1
Selected: U
🧠 Explicação simples: Para garantir alta disponibilidade de 99,99% no Azure, você precisa usar Zonas de Disponibilidade. Elas são como centros de dados separados fisicamente dentro da mesma região — se uma falhar, a outra continua funcionando. 📦 Estratégia proposta: 1 máquina virtual distribuída entre 2 zonas de disponibilidade. Isso pode ser feito usando VMs em um conjunto de disponibilidade (Availability Set) ou escalando com instâncias redundantes em zonas diferentes. 💡 Mesmo com mínimo de VMs, ao usar duas zonas, você atende ao requisito de 99,99% de disponibilidade, porque o Azure garante essa SLA quando os recursos estão
Meesquared
👍 3
Selected: B
A single VM cannot be distributed across two availability zones. To achieve 99.99% availability, you need at least two VMs deployed across two availability zones. Correct Strategy: ✅ Deploy two VMs in two availability zones (one VM per zone) and use a load balancer if required. This ensures that if one zone fails, the other VM in the other zone will still be available.
kahla
👍 1
Selected: A
Azure guarantees a 99.99% SLA (4 nines) for VMs if they are deployed across two or more availability zones. This means the application will remain available even if one zone goes down. To get this SLA: You must deploy at least two virtual machines spread across two availability zones OR Use VM scale sets with zone redundancy.
mitddgr
👍 1
Selected: B
to ensure 99.99 SLA you need 2 VMs in 2 availability zones
arjunyv2022
👍 1
Selected: B
the given solution only includes one VM, it does not meet the 99.99% availability requirement. The correct solution is to deploy at least two VMs across two Availability Zones.
DagKar
👍 2
Selected: B
B. No The solution does not meet the goal. To achieve a guaranteed availability of 99.99% in Azure, you need to deploy the virtual machines across at least two availability zones. Using only one availability zone means that if there is an issue in that zone, both virtual machines could be affected, leading to downtime and not meeting the 99.99% availability requirement. Azure provides 99.99% availability for virtual machines only when they are distributed across two or more availability zones, ensuring redundancy and failover capabilities. Therefore, the proposed strategy with two VMs in a single availability zone would not be sufficient.
skjena
👍 1
SLA for Virtual Machines Last updated: July 2020 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. For all Virtual Machines that have two or more instances deployed in the same Availability Set or in the same Dedicated Host Group, we guarantee you will have Virtual Machine Connectivity to at least one instance at least 99.95% of the time. For any Single Instance Virtual Machine using Premium SSD or Ultra Disk for all Operating System Disks and Data Disks, we guarantee you will have Virtual Machine Connectivity of at least 99.9%. For any Single Instance Virtual Machine using Standard SSD Managed Disks for Operating System Disk and Data Disks, we guarantee you will have Virtual Machine Connectivity of at least 99.5%. For any Single Instance Virtual Machine using Standard HDD Managed Disks for Operating System Disks and Data Disks, we guarantee you will have Virtual Machine Connectivity of at least 95%. Answer correct.
BinuRaj
👍 12
Answer correct. SLA for Virtual Machines Last updated: July 2020 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. For all Virtual Machines that have two or more instances deployed in the same Availability Set or in the same Dedicated Host Group, we guarantee you will have Virtual Machine Connectivity to at least one instance at least 99.95% of the time. For any Single Instance Virtual Machine using Premium SSD or Ultra Disk for all Operating System Disks and Data Disks, we guarantee you will have Virtual Machine Connectivity of at least 99.9%. For any Single Instance Virtual Machine using Standard SSD Managed Disks for Operating System Disk and Data Disks, we guarantee you will have Virtual Machine Connectivity of at least 99.5%. For any Single Instance Virtual Machine using Standard HDD Managed Disks for Operating System Disks and Data Disks, we guarantee you will have Virtual Machine Connectivity of at least 95%.
AntonioTech
👍 1
The answer seems to be B. No Deploying one virtual machine and two availability zones does not meet the goal of achieving a guaranteed availability of 99.99 percent. To achieve such a high level of availability, you typically need to distribute your application across multiple instances in multiple availability zones or sets.
Cambo995
👍 8
Selected: B
+2 VM on +2 AZ = 99.99% +2 VM on 1 AZ = 99.95%
james2033
👍 2
What is "LOB"?
Cambo995
👍 6
It stands for Line of Business. LOB applications refer to software applications that are specifically designed to support the core business functions of an organization
aerumna
👍 2
You need at least 2 VM in 2 different AZ. With a single VM having multiple AZ has no effect, because (of course?) VM cannot spans AZs
Kanders
👍 1
B. No - You will need a minimum of two VMs across two availability zones to reach 99.99 %
Luansi
👍 1
Selected: B
https://azure.microsoft.com/en-us/support/legal/sla/virtual-machines/v1_9/ For any Single Instance Virtual Machine using Premium SSD, Ultra Disk or Premium SSD v2 for all Operating System Disks and Data Disks, we guarantee you will have Virtual Machine Connectivity of at least 99.9%. CONCLUSSION: For a single VM instance you only have to see the disk, not availability zones.
MarMar2022
👍 1
Selected: B
B definetly
janely03
👍 2
The answer is NO. https://docs.microsoft.com/en-us/azure/architecture/framework/services/compute/virtual-machines/operational-excellence 95% SLA for single instance virtual machines using Standard HDD-Managed Disks for OS and Data disks. 99.5% SLA for single instance virtual machines using Standard SSD-Managed Disks for OS and Data disks. 99.9% SLA for single instance virtual machines using Premium SSD or Ultra Disk for all OS and Data disks. 99.95% SLA for all virtual machines that have two or more instances in the same Availability Set or Dedicated Host Group. 99.99% SLA for all virtual machines that have two or more instances deployed across two or more Availability Zones in the same region.
manraj
👍 5
Selected: B
MIN 2 VM AND 2 AZ FOR 99.99 %
arjaycee
👍 1
I'm going to say NO because it has to be as least 2 VMs and 2 AZs to achieve 99.99%
jrmunoza
👍 2
The question says "strategy requires as little virtual machines and availability zones as possible." so is not correct because they will use two VM. One VM with two instances and two availability zones could be the correct answer
RaySmith
👍 1
Answer is: A
kate_py
👍 47
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. "SLA for Virtual Machines Last updated: July 2020", https://azure.microsoft.com/en-us/support/legal/sla/virtual-machines/v1_9/ That was cited in: https://docs.microsoft.com/en-us/azure/availability-zones/az-overview after ' With Availability Zones, Azure offers industry best 99.99% VM uptime SLA. '
Petergrayston
👍 1
Nevermind, the answer is correct. "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."
Petergrayston
👍 2
How can this be Yes, "You need to make sure that the strategy requires as little virtual machines and availability zones as possible."
Turak64
👍 3
Read the rest of the question, the requirement is 99.99% SLA which can not be achieved with just one VM
iwarakorn
👍 3
Answer is Yes 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.
Comments & Corrections
No comments yet — spotted an error or have a note? Share it below.
Expert Analysis
Why the Answer Is Correct
The solution fails because it includes only one virtual machine. According to Microsoft's official SLA documentation, the 99.99% uptime guarantee for Virtual Machines applies specifically when you have "two or more instances deployed across two or more Availability Zones." A single VM instance, even if placed in an Availability Zone, does not qualify for this tier because there is no redundancy at the instance level within that zone. To meet the goal, you must deploy at least two VMs (one per zone) to ensure connectivity to at least one instance if a zone fails.Why the Other Options Are Wrong
Option A is incorrect because the proposed strategy of one VM and two zones is technically impossible to execute as described (a single VM resides in one zone) and mathematically insufficient for the 99.99% SLA. The 99.99% threshold is not achievable with a single instance; the best you can get with a single VM in a single zone is typically lower (e.g., 99.9% for single-instance). Therefore, the requirement for "as little VMs... as possible" while hitting 99.99% dictates a minimum of two VMs across two zones.Community Comment Notes
Community consensus strongly supports Option B, citing the official Azure SLA page which explicitly states the condition: "For all Virtual Machines that have two or more instances deployed across two or more Availability Zones... we guarantee... 99.99% of the time." Users like Kate_py and BinuRaj emphasize that a single VM cannot trigger this guarantee. Meesquared correctly notes that a single VM cannot be distributed across two zones, highlighting the architectural constraint.Official Reference
Exam Strategy
Memorize the specific SLA percentages for Azure services. For VMs, remember that 99.99% requires Multi-Instance + Multi-Zone. Single-instance VMs generally cap at 99.9% or lower depending on configuration.
Frequently Asked Questions
Can a single VM be spread across multiple availability zones?
No. A single virtual machine instance is hosted within a specific physical location, which corresponds to one Availability Zone. It cannot span multiple zones.
What is the minimum number of VMs for 99.99% SLA?
You need at least two VM instances. Each instance should ideally reside in a different Availability Zone to ensure redundancy against zone-level failures.
Related Analysis
Practice All AZ-900 Questions
Access 90 questions with complete answers and detailed explanations.
View Full AZ-900 Practice Test →