Exam AZ-305 topic 4 question 54 discussion

I prefer B. Costs must be minimized. Failover must be provided if a single server fails. > No information is given that would recommend to use premium storage. > We need protection if a server fails, Failover Cluster provides availability at the instance level whereas Availability Groups provides failover at the Database Level. About AG. Because availability groups only provide database-level, and not instance-level, protection, anything not captured in the transaction log or configured in the database will need to be manually synchronized for each secondary replica. Some examples of objects that must be synchronized manually are logins at the instance level, linked servers, and SQL Server Agent jobs. About FC Databases are only available after recovery is complete, so recovery time will depend on many factors, and will generally be longer than failing over an availability group. The tradeoff is that when you fail over an availability group, there may be additional tasks required to make a database usable, such as enabling a SQL Server Agent job.

This question appeared in todays exam (29/01/23) Answered C Scored 903

Minimizing cost seems to be the priority. only B is standard, and the rest are premium which makes it more expensive!

When comparing the cost of an Azure SQL Database Always On Failover Cluster (FCI) to an Azure SQL Database Availability Group (AG), the pricing is generally similar, but FCI can potentially be more expensive due to the requirement for shared storage, which adds an additional cost layer compared to AG that does not need shared storage for replication; meaning, with AG you only pay for the compute resources used by the replicas, while with FCI you also pay for the shared storage infrastructure involved in the cluster. Answer :C

Always On Availability Groups provide better scalability and flexibility in a cloud environment. DNN (Distributed Network Name) allows for improved networking flexibility, which is beneficial in Azure. Although premium storage disks increase costs, they provide the necessary performance to ensure fast failover times, which can be crucial for maintaining high availability. Thus, option C strikes a good balance between high availability, performance, and cost management in an Azure environment.

Based on this article i would choose C https://learn.microsoft.com/en-us/azure/azure-sql/virtual-machines/windows/availability-group-distributed-network-name-dnn-listener-configure?view=azuresql

The distributed network name (DNN) replaces the virtual network name (VNN) as the connection point when used with an Always On failover cluster instance on SQL Server VMs. This negates the need for an Azure Load Balancer routing traffic to the VNN, simplifying deployment, maintenance, and improving failover.

Failover Cluster provides availability at the instance level Minimize Cost --> Standard storage

C. an Always On availability group that has premium storage disks and a distributed network name (DNN). The Always On Availability Group with a Distributed Network Name (DNN) would be the better choice due to the faster failover time, which aligns with the requirement of minimizing failover time if a single server fails. The DNN listener in this case doesn't require an Azure Load Balancer to reroute traffic, resulting in quicker failovers compared to the VNN listener. This is a great choice when high availability and minimal failover time are prioritized.

Passed exam today with 979, and this question was on the exam, I am confident the correct answer is C.

C is the answer. https://learn.microsoft.com/en-us/azure/azure-sql/virtual-machines/windows/availability-group-distributed-network-name-dnn-listener-configure?view=azuresql With SQL Server on Azure VMs in a single subnet, the distributed network name (DNN) routes traffic to the appropriate clustered resource. It provides an easier way to connect to an Always On availability group (AG) than the virtual network name (VNN) listener, without the need for an Azure Load Balancer.

C. an Always On availability group that has premium storage disks and a distributed network name (DNN)

answer is C

DNN is recommended by MS