Available Sets

Question 1

What are availability sets used for?

Answer 1

Availability sets provide high availability for non-identical or unique virtual machines within a single data center or zone.

Question 2

How do availability sets differ from VM Scale Sets?

Answer 2

Availability sets are for unique VMs, do not have autoscaling, and are relevant within a single data center or zone, unlike VM Scale Sets which handle identical VMs and can scale across regions.

Question 3

What is the purpose of fault domains in availability sets?

Answer 3

Fault domains ensure high availability by grouping VMs on separate server racks with distinct power and networking sources to prevent a single point of failure.

Question 4

What are update domains in availability sets?

Answer 4

Update domains are groups of hypervisors with the same maintenance window, allowing VMs to be placed on different hypervisors to minimize downtime during maintenance updates.

Question 5

How does an availability set help in maintaining high availability?

Answer 5

By placing VMs in different fault and update domains, an availability set ensures that VMs are distributed across multiple server racks and maintenance schedules, reducing the impact of failures or maintenance updates on overall availability.

Question 6

What is the maximum limit for update domains in an Azure availability set?

Answer 6

Azure allows configuring up to 20 separate update domains for VMs within an availability set, while fault domains are limited to a maximum of three.