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What is an example of a distributed availability group?
For example, if the AG containing the read/write primary replica is SQL Server 2016, but you want to upgrade/migrate to SQL Server 2017 or later, the other AG participating in the distributed AG can be configured with SQL Server 2017.
How to deploy a distributed SQL Server always on?
You should follow previous articles, An Overview of distributed SQL Server Always On Availability Groups, and Deploy a distributed SQL Server Always On Availability Group in the series of SQL Server Always On Availability groups and configure a distributed availability group before you go further in this article.
What are always on availability groups in SQL Server 2016?
This is the 12th article in the series of SQL Server Always On Availability Groups. SQL Server 2016 provides a new feature Distributed Availability Group for disaster recovery purposes. It is a particular type of availability group that helps access the multiple failover clusters.
How many replications can I have in distributed SQL Server?
Scale-out readable replicas with distributed availability groups: In a traditional SQL Server Always On Availability Groups configuration, SQL Server 2019 allows 1 primary and up to 8 secondary replicas. In a distributed configuration, we have two availability groups, so it supports up to 16 secondary replicas.
How to host an availability replica for an availability group?
To host an availability replica for an availability group, a server instance must possess a database mirroring endpoint. The server instance uses this endpoint to listen for Always On availability groups messages from availability replicas hosted by other server instances.
Do you need to enable always on availability groups?
The Always On availability groups feature must be enabled on each of the instances of SQL Server. For more information, see Enable and Disable Always On Availability Groups (SQL Server). The accounts under which SQL Server is running must be correctly configured. Do the accounts have the correct permissions?
When to specify endpoint URL for availability replica?
Therefore, the port you specify in the endpoint URL when you specify an availability replica will always direct incoming messages to the server instance whose endpoint is associated with that port. IIn the endpoint URL, only the number of the port identifies the server instance that is associated with the mirroring endpoint on the target computer.