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What does an always-on availability group do?
Availability Groups establish mirroring which is scoped to the database. If you are using contained databases and do not use the SQL Agent, linked servers, credentials, proxies, or any other server level object, then jump down to the next question.
Can you off-load your backups with always on availability groups?
With the mandate of snapshot isolation being used on your secondary replicas, it is critical that the business, and the application doing the reads, are OK with the potential for phantom inserts and transactions which do not guarantee repeatable reads. Can you off-load your backups?
Do you need windows fail over cluster for availability groups?
A Windows Fail-over Cluster was not a requirement for Database Mirroring, the feature that serves as the foundation for Availability Groups. With AGs, a typical multi- data center architecture might look like this. The most important aspect of this change in requirements is how you configure quorum.
What does asynchronous commit mode mean in Java?
Take the asynchronous commit mode for a moment. This mode means that the transactions will be asynchronously sent from the primary replica to all secondary replicas. At any given moment, your secondary replicas might be different due to latency. When it is small, delay can be understood and easily accepted for most applications.
How many replicas does an availability group support?
Each availability group supports one primary replica and up to eight secondary replicas. For more information, see Overview of Always On Availability Groups (SQL Server). Each availability replica must reside on a different node of a single Windows Server Failover Clustering (WSFC) cluster.
How many databases can a availability group support?
An availability group supports a set of read-write primary databases and one to eight sets of corresponding secondary databases. Optionally, secondary databases can be made available for read-only access and/or some backup operations.
How to monitor the performance of SQL server availability groups?
If the capture process is not able to scan and enqueue the messages fast enough, the log send queue builds up. SQL Server:Availability Replica > Bytes Sent to Replica\\sec, which is an aggregation of the sum of all database messages queued for that availability replica.