Ali Shaik's Database Diary

      A distributed availability group (AG) is a special type of availability group that spans two separate availability groups. Distributed availability groups are available starting with SQL Server 2016. The availability groups that participate in a distributed availability group don't need to be in the same location. They can be physical, virtual, on-premises, in the public cloud, or anywhere that supports an availability group deployment. The following figure shows a high-level view of a distributed availability group that spans two availability groups (AG 1 and AG 2), each configured on its own WSFC. The distributed availability group has a total of four replicas, with two in each availability group. Each availability group can support up to the maximum number of replicas, so a distributed availability can have up to 18 total replicas.       However, data movement is slightly different within distributed availability groups compared to a ...

1.What are the prerequisites for setting up AlwaysOn? 2.How do you set up replication in AlwaysOn environment? 3.How do you manage replication during Windows patching or failover if replication has been set up in AlwaysOn? 4.How do you sync logins in AlwaysOn? 5.How do you sync users in AlwaysOn secondary? 6.How do you add database files in AlwaysOn? 7.How do you perform an in-place upgrade of SQL Server in a AlwaysOn environment? 8.What is the procedure for SQL Server patching in AlwaysOn? 9.How do you failover a mirror server if replication has been set up? 10.What is the SPN concept in AlwaysOn? 11.What is file share in AlwaysOn? 12.How do you create multiple AlwaysOn listeners? 13.How do you check latency in AlwaysOn? 14.What is the command used to check latency in replication without using GUI? 15.What are DNS issues in AlwaysOn? 16.If a user is connecting to the primary and not able to connect to the secondary, and the secondary is in read-only mode, how do you fix the issue in A...

  SQL Server 2019 Read Write Routing URL  SQL Server 2019 introduces a new feature for Availability Groups that addresses the challenges of read/write connection redirection. With this feature, client applications can connect to any replica of the Availability Group, and the connection will be automatically redirected to the primary replica based on the Availability Group configuration and the connection intent specified in the connection string.   In previous versions of SQL Server, an administrator had to configure the Availability Group listener (and the corresponding cluster resource) to direct SQL Server traffic to the primary replica to ensure that clients were reconnected to the active primary node in the event of failover. However, not all cluster technologies that support SQL Server Availability Groups offered a listener-like capability, making this process more complicated.   The secondary-to-primary replica connection redirection feature in SQL Ser...

  Differences between the Developer, Standard, and Enterprise Editions for SQL Server Always On Availability Groups SQL Server Always On Availability Groups is a high-availability and disaster recovery solution that is available in SQL Server Developer, Standard, and Enterprise Editions. However, the specific features and limitations of Always On Availability Groups may differ across these editions. Maximum number of replicas: Developer Edition supports up to two replicas (primary and one secondary). Standard Edition supports up to two replicas (primary and one secondary). Enterprise Edition supports up to eight replicas (one primary and seven secondary). Readable secondary replicas: Developer Edition supports readable secondary replicas for reporting or backup purposes. Standard Edition supports readable secondary replicas for reporting or backup purposes. However, it does not support read-only routing. Enterprise Edition supports both readable secondary replicas and read-only rou...