“AlwaysOn,” one of the most well-known features added to SQL Server 2012, utilizes existing HA/DR features and offers extra features like Availability Groups.
Top 10 Scenarios Based Interview Questions of SQL Server Always ON || SQL AAG Interview Questions ||
Q. You discover that the failover time exceeds your recovery time objective (RTO) after an automatic failover or a planned manual failover on an availability group. Or, you discover that the time required to estimate the failover time of a secondary replica with synchronous commits (like an automatic failover partner) using the method described in Monitor Performance for AlwaysOn Availability Groups, exceeds your RTO. Could you list some potential causes for the failover time exceeding your RTO?
Q. Consider that one of our premium production servers is a member of the AlwaysOn Availability Group. You notice that a certain time of day is when CPU usage is at its highest. You performed an RCA and discovered that the highest CPU usage is coming from the backup process because backup compression is enabled. What do you recommend right now? Do we have any backup features?
“AlwaysOn,” one of the most well-known features added to SQL Server 2012, utilizes existing HA/DR features and offers extra features like Availability Groups. One can easily anticipate scenario-based questions in today’s technical interviews. This article is for SQL Server DBAs who are preparing for interviews. It includes basic and advanced level SQL DBA AlwaysOn scenario-based interview questions and answers. Here are the scenario based questions.
In order to recover a database (database ID 1), SQL Server must be terminated. The database is either a system database or a user database that cannot be closed. Restart SQL Server. In case a second startup, repair, or restore doesn’t help the database recover SQL Trace was stopped due to server shutdown. Trace ID = ‘1’. There is no user action necessary; this is only an informational message. ).
Q. When you perform a forced manual failover on an availability group to an asynchronous-commit secondary replica, you discover that the amount of data loss exceeds your RPO. Or, you discover that the RPO is exceeded when you use the method in Monitor Performance for AlwaysOn Availability Groups to determine the potential data loss of an asynchronous-commit secondary replica. What are the potential causes of data loss that exceeds your recovery point goal?
A new feature added to SQL Server 2014 that directs read-only workloads to the first secondary replica that becomes available that is listed in a predefined routing list, provided the application explicitly specifies the Application Intent=Readonly parameter.
What are the synchronization methods employed by the SQL Server Availability Group to maintain consistency between the replicas?
The High Availability and Disaster Recovery plan assists in ensuring that our database servers, which house the crucial operational data for the business and support its primary systems, will be operational for the greatest amount of time with the least amount of downtime.
a collection of databases hosted in a SQL Server instance, referred to as the primary replica, which are copied to and synchronized with up to eight servers, referred to as the secondary replicas.
Why is setting up a SQL Server Always On Availability Group with two replicas and configuring the quorum in Node Majority mode regarded as a best practice?
I’ve published a variety of topics’ worth of SQL Server Interview Questions and Answers. To access all of the SQL Server Interview Questions and Answers on various topics that have been posted on this website, click the attached link. I’ll be posting SQL Server Alwayson Interview Questions and Answers right here.
Answer: There are many advantages to performing backups on a secondary replica in order to relieve the primary production server of the backup workload. From secondary replicas, we can run log backups and copy_only full backups. To run these backups from the secondary replica, we must modify the Backup Preferences setting in the AOAG configuration. To learn more about AOAG Backup Preferences and how it functions, see the article below.
Answer: In order to restore a database that is a member of an availability group, we must first remove it from the group. Once the database has been removed from the availability group, you can restore it and later add it back. To learn how to restore an AOAG database, read the attached article.
What are the differences between a SQL Server Availability Group and Replication?
The key distinctions between an Availability Group and Replication are listed below.
FAQ
What is difference between failover cluster and AlwaysOn?
Unlike a failover cluster, AlwaysOn availability groups (AAGs) do not share storage because SQL Server uses log shipping to replicate data from the primary database to the instances of the backup databases.
How do you failover in AlwaysOn availability groups step by step?
Connect to a server instance hosting a backup replica of the availability group that needs to be failed over in Object Explorer. Expand the server tree. Extend the Availability Groups node and the Always On High Availability node. Failover can be chosen by right-clicking the availability group to be switched to.
How automatic failover happens in AlwaysOn availability groups?
In an automatic failover set, Always On Availability Groups keeps an eye on the condition of both replicas. The health state of the availability group is changed to CRITICAL if either replica fails. Automatic failover is not possible if the secondary replica fails because the target is not available.
How many IP address needed for SQL Server AlwaysOn?
Each cluster node’s eth0 elastic network interface needs two secondary IPs. Reminder: Only add one secondary IP address to each cluster node’s elastic network interface if you don’t intend to deploy a SQL Group Listener. 1.
